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Write the equation of the line that passes through the point (7,-2) and has a slope of

-3
a) in slope-intercept form
b) in standard form.

User Keasha
by
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2 Answers

2 votes
i only know how to do a, so i hope i can help a little bit.
y=mx+b
-2=-3(7)+b
-2=-21+b
b=19
so your equation is y=-3x+19
i hope this helps!!
User Jesper Blaase
by
3.9k points
6 votes

Answer:

Explanation:

a) The equation of a straight line can be represented in the slope intercept form as

y = mx + c

Where

m = slope = (change in the value of y in the y axis) / (change in the value of x in the x axis)

The slope of the equation is given as - 3

The line passes through the point (7,-2)

To determine the intercept, we would substitute m = - 3, x = 7 and y = -2 into y = mx + c. It becomes

- 2 = - 3 × 7 + c = - 21 + c

c = - 2 + 21 = 19

The equation becomes

y = -3x + 19

b) the standard form is expressed as

Ax + by = C

We would substitute x = 7, y = - 2 and m = - 3 into the point slope equation, y - - 2 = - 3(x - 7)

y + 2 = - 3x + 21

3x + y = 21 - 2

3x + y = 19

The standard form is 3x + y = 19

User Raz Buchnik
by
3.9k points