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Find the slope and the y-intercept of the line.
y= 3/4-1/5x

User Salvin
by
3.2k points

2 Answers

6 votes

Answer:

Slope = -0.400/2.000 = -0.200

x-intercept = 15/4 = 3.75000

y-intercept = 15/20 = 3/4 = 0.75000

Explanation:

* BE AWARE, THIS ANSWER IS NOT TO BE PLAGERIZED AS IT IS CONSIDERED CHEATING IF THIS IS A TEST OR HOMEWORK QUESTION, MOST LIKELY IT IS* - Purpose is to help understanding of the concept.

Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

y-(3/4-1/5*x)=0

STEP 1:

simplify 1/5

Equation at the end of step 1:

y -(3/4-(1/5• x)) = 0

Step 2:

Simplify 3/4

Equation at the end of step 2:

y-)(3/4-x/5)=0

Step 3:

Calculating the Least Common Multiple :

ind the Least Common Multiple

The left denominator is : 4

The right denominator is : 5

Number of times each prime factor

appears in the factorization of:

Prime

Factor Left

Denominator Right

Denominator L.C.M = Max

{Left,Right}

2 2 0 2

5 0 1 1

Product of all

Prime Factors 4 5 20

Least Common Multiple:

20

Calculating Multipliers :

3.2 Calculate multipliers for the two fractions

Denote the Least Common Multiple by L.C.M

Denote the Left Multiplier by Left_M

Denote the Right Multiplier by Right_M

Denote the Left Deniminator by L_Deno

Denote the Right Multiplier by R_Deno

Left_M = L.C.M / L_Deno = 5

Right_M = L.C.M / R_Deno = 4

Making Equivalent Fractions :

3.3 Rewrite the two fractions into equivalent fractions

Two fractions are called equivalent if they have the same numeric value.

For example : 1/2 and 2/4 are equivalent, y/(y+1)2 and (y2+y)/(y+1)3 are equivalent as well.

To calculate equivalent fraction , multiply the Numerator of each fraction, by its respective Multiplier. L. Mult. • L. Num. 3 • 5

—————————————————— = —————

L.C.M 20

R. Mult. • R. Num. x • 4

—————————————————— = —————

L.C.M 20

Adding fractions that have a common denominator :

3.4 Adding up the two equivalent fractions

Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

3 • 5 - (x • 4) 15 - 4x

——————————————— = ———————

20 20

Equation at the end of step

3

:

(15 - 4x)

y - ————————— = 0

20

STEP

4

:

Rewriting the whole as an Equivalent Fraction :

4.1 Subtracting a fraction from a whole

Rewrite the whole as a fraction using 20 as the denominator :

y y • 20

y = — = ——————

1 20

Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

4.2 Adding up the two equivalent fractions

y • 20 - ((15-4x)) 20y + 4x - 15

—————————————————— = —————————————

20 20

Equation at the end of step

4

:

20y + 4x - 15

————————————— = 0

20

STEP

5

:

When a fraction equals zero :

5.1 When a fraction equals zero ...

Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.

Here's how:

20y+4x-15

————————— • 20 = 0 • 20

20

Now, on the left hand side, the 20 cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :

20y+4x-15 = 0

Equation of a Straight Line

5.2 Solve 20y+4x-15 = 0

Tiger recognizes that we have here an equation of a straight line. Such an equation is usually written y=mx+b ("y=mx+c" in the UK).

"y=mx+b" is the formula of a straight line drawn on Cartesian coordinate system in which "y" is the vertical axis and "x" the horizontal axis.

In this formula :

y tells us how far up the line goes

x tells us how far along

m is the Slope or Gradient i.e. how steep the line is

b is the Y-intercept i.e. where the line crosses the Y axis

The X and Y intercepts and the Slope are called the line properties. We shall now graph the line 20y+4x-15 = 0 and calculate its properties

Graph of a Straight Line :

Calculate the Y-Intercept :

Notice that when x = 0 the value of y is 3/4 so this line "cuts" the y axis at y= 0.75000

y-intercept = 15/20 = 3/4 = 0.75000

Calculate the X-Intercept :

When y = 0 the value of x is 15/4 Our line therefore "cuts" the x axis at x= 3.75000

x-intercept = 15/4 = 3.75000

Calculate the Slope :

Slope is defined as the change in y divided by the change in x. We note that for x=0, the value of y is 0.750 and for x=2.000, the value of y is 0.350. So, for a change of 2.000 in x (The change in x is sometimes referred to as "RUN") we get a change of 0.350 - 0.750 = -0.400 in y. (The change in y is sometimes referred to as "RISE" and the Slope is m = RISE / RUN)

Slope = -0.400/2.000 = -0.200

Geometric figure: Straight Line

Slope = -0.400/2.000 = -0.200

x-intercept = 15/4 = 3.75000

y-intercept = 15/20 = 3/4 = 0.75000

User David Leon
by
3.7k points
10 votes

Answer:

Slope = -1/5

y-intercept = 3/4

Explanation:

Equation of Straight Line in the Form y=mx+c

where m is the Slope and c is the y-intercept.

User Jimidy
by
3.3k points