Let's write T for Teagan's score and E for Emma's score.
Also, let's write an equation
E = 2T + 4
E = 3
2T + 4 = 3
subtract 4 from both sides
2T = -1
divide both sides by 2
T = -1/2
To see of this is correct:
2T + 4 = 3
2(-1/2) + 4 =?= 3
-1 + 4 =?= 3
3 = 3
Hope this helps
We are going to base the answer off of the y=mx+b form where m represents slope and b represents the y-intercept.
First, we know that b must be -1 because the line hits the y-axis when y is -1
So this leaves us with either the first or second choice
Then we choose two points to find the slope. I am using (0,-1) and (1,2). If you count the boxes, the y-value increases by 3 as the x-value increases by 1. So the slope is 3/1 or 3.
So then we know the answer is y=3x-1
Hope this helps
15%
amount error is guess subtract actual amount 198-172 = 26
26/172 = 0.15
0.15 x100 = 15%