Question

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

and has a slope of -5.
A
0-7
O-1
01
07
8
00..
7
6
5
What is the
is also on the line?
-2-1 1 2 3 4 5 6 7 8 X
do to do
value of a if the point (a, 2)

Answer 1

The numbers appear random, not as valid points. I'll develop the equation for the line. That can be used to determine which points lie on the line.

y = -4x - 3

Explanation:

The slope-intercept form of a straight line equation is y = mx + b, where m is the slope and b is the y-intercept (the value of y when x = 0)

We are given the slope (m = -5)

We can write y = -5x + b

To find b, enter the given data point and solve for b:

y = -5x + b for (-2,7)

7 = -5*(-2) + b

b = -3

The equation is y = -5x - 3

Use this equation to determine which points are valid. E.g. enter 0 for x and see if y matches the answer option.

The value of a for point (a, 2):

y = -5x - 3

2 = -5a - 3

5 = -5a

a = -1