F(13) means x equals 13.
Replace x in the equation with 13 and solve:
-13 + 3 = -10
F(13) = -10
Answer:

Step-by-step explanation:
Given: 
To solve this equation, we need to isolate
on one side of the equation algebraically. I see that we have like terms, but they are on opposite sides of the equal sign. Let's add
to both sides.

To isolate x, divide both sides by 7.

Since we already know that the slope is 0, x cancels out in the equation.
y = mx + b → y = b
We just need to find the y-intercept. Using the coordinate (2, 4) we can substitute with y.
4 = b
Hence, the answer is b) y = 4
Hope This Helped! Good Luck!
Rationalise the denominator of 1/2√3
Detailed answer is in the image attached.
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