Question

Find the value of b if the graph of y=-3x+b goes through the
point.
A(-2,4)

Answer 1

• The value of b is -2.

Explanation:

I have solved this with the help of a coordinate plane.

• First, I plotted the point (-2,4).
• Next, I tested the y-intercept and found that the equation of the line that crossed the point is y = -3x - 2.

Now, if we compare the equation and the formula:

• (y = mx + b) = (y = -3x - 2)

We can clearly see that the value of b is -2.

Hence, the value of b is -2.

Answer 2

b = -2

Explanation:

y=-3x+b

y = -3( x + b/3 )

∵ from this we get gradient is -3.

use formula:

y -y1 = m (x - x1 )

y - 4 = -3 ( x - - 2)

y -4 = -3( x + 2)

y = -3x - 6 + 4

y = -3x -2

if we compare both we get to understand b = -2