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If f(x) = 3x +x^2, what is f(-2)?

f(-2) = 3(-2) + (-2)2 = -6 + 4 = 2First you need to substitute -2 for each value of x in the function. Then you need to simplify the expression by multiplying -2 by 3 and by squaring -2. (Hint...

Answered by William B. Maths tutor
4201 Views

Add the fractions 2/5 + 3/7.

We must find a common denominator between the fractions to be able to add them (the bottom numbers must be the same). A common denominator of 5 and 7 is 35. To get to 35 from 5 we multiplied by 7, therefo...

Answered by Alex L. Maths tutor
9848 Views

Find the length of AB from the right-angle triangle ABC. Angle ACB = 40 degrees and side BC = 15cm.

Label each of the sides using the angle BCA. Therefore, AC = Adjacent, BC = Hypotenuse and AB = Opposite. Use the anagram SohCahToa to identify the side that we have (BC) and the side we are looking for (...

Answered by Alex L. Maths tutor
3081 Views

Find the coordinates of the stationary point of y = x^2 + x - 2

At a stationary point, the gradient/slope of the graph is 0. To find the gradient of y, we differentiate with respect to x.This gives us dy/dx = 2x + 1. Since we want to find where the gradient is 0, we s...

Answered by Martin C. Maths tutor
3881 Views

3x + 4y + 7z = 12. x=2 and y=-1, what is the value of z to 2 dp?

first you sub in the values you know so3(2) + 4(-1) + 7z =12then you simply the equation6-4+7z=122+7z=12then you put all the letter values on one side and all the numbers on the other12-2= 7zthen simplify...

Answered by Emily P. Maths tutor
2637 Views

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