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What is the equation of the line that passes through
(-2, 4) and (2, 7)?

1 Answer

7 votes

Answer:


y=(3)/(4)x+(11)/(2)

Explanation:

Hi there!

We want to find the equation of the line that passes through (-2, 4) and (2, 7).

The most common way to write the equation of the line is in slope-intercept form, which is y=mx+b, where m is the slope and b is the y intercept.

First, let's find the slope of the line.

The slope, calculated from two points is given as the formula
(y_2-y_1)/(x_2-x_1), where
(x_1, y_1) and
(x_2, y_2) are points.

We have two points, which is needed to find the slope, but let's label their values to avoid confusion.


x_1=-2\\y_1=4\\x_2=2\\y_2=7

Now substitute those values into the formula.

m=
(y_2-y_1)/(x_2-x_1)

m=
(7-4)/(2--2)

Simplify

m=
(7-4)/(2+2)

m=
(3)/(4)

So the slope of the line is
(3)/(4).

Substitute that value as m in y=mx+b

y=
(3)/(4)x+b

Now we need to find b

As the equation passes through both (-2, 4) and (2, 7), we can substitute the values of either one of them in the equation to solve for b

Taking (-2, 4) for example,

Substitute -2 as x and 4 as y:

4=
(3)/(4)(-2)+b

Multiply

4=
-(3)/(2)+b

Add -3/2 to both sides


(11)/(2) = b

Substitute that value into the equation

y=
(3)/(4)x+(11)/(2)

Hope this helps!

User Matteo Monti
by
5.3k points