Step by step
The question
Question: which starts higher: function A, x: 2, 3, 4; y: 7, 10, 13, or function B, y = 2x + 2?
A: x: 2, 3, 4; y: 7, 10, 13
= B: y = 2x + 2
The start value is y when x is 0.
The bigger one starts higher.
starts higher = bigger start value
1 Start value of A
Going back to x = 0, y is 1.
= b = 1
2 Start value of B
In y = m x plus b, b is the number added: 2.
= y = 2x + 2: b = 2
3 Compare
2 is bigger.
So function B starts higher.
= 1 < 2 → B starts higher
Careful!
Function A grows faster.
But it starts lower.
Careful: the faster one is not the higher start
4 Check
Let's check: both lines on one grid.
Line B crosses the y-axis higher.
So the answer is right!
Let's look back.
First: start value of A.
Then: start value of B.
Then: compare.
Last: check.
Answer
Careful: the faster one is not the higher start