Write an equation that represents the line.
Use exact numbers.

Step-by-step explanation:

The equation is y = mx +c

since we know that m is the gradient, we look at the two points on the line and draw two lines as shown in the picture above.

the yellow line goes down 2 squares

and the red line goes left once

so it's 2 over 1

2÷ 1 = 2

so the gradient equals 2

now for the c

c means the y intercept. so all you have to do, is find where the line hits the y axis.

In this case it's -3

lastly, we need to put it in the equation

y= mx +c

y= 2x -3

and that should be all

I hope that helped xx

you didn't post any answer choices, so its not 100% clear what your teacher is looking for

however, log(15/7) is equivalent to log(15) - log(7)

i'm using the rule log(x/y) = log(x) - log(y)