Question

Which equation describes the line with a slope of -3 that contains the point (2,4)?

Answer 1

C. is the correct option

Explanation:

When we find the equation using the point and slope formula, we get y=-3x+10

As you can see, that doesn't match any of the answers, since it is in the point-slope formula.

We can start solving all the equations to rule out the correct one, but to save yourself from reading all of this, I'll just do there C.

For this equation, we will distribute the 3, and then add 4 to both sides.

y-4=-3(x-2) ---> y-4=-3x+6 ---> y-4(+4)=-3x+6(+4) ---> y=-3x+10

This leads back to the original equation so we know it is correct.

Answer 2

Answer: y = 2x - 11

Explanation:

A linear equation has the following form.

y = a . x + b

where,

y: independent variable

a: slope

x: independent variable

b: y-intercept

The slope is 2, so a is 2. The ordered pair (4, -3) means that when x takes the value 4, y takes the value -3. We can replace these values in the general equation to find the y-intercept.

y = a . x + b

-3 = 2 . 4 + b

b = -11

The linear equation is

y = 2x - 11