1. 8x^2 + 10x - 9
2. 3x^4 - 14x^2 - 9
3. 4x^2 + 5x - 9
4. 8x^2 + 10x - 18

4.

Step-by-step explanation:

(x^2 + 7x - 9) + (3x^2 - 2x) + (x^2 + 7x - 9) + (3x^2 - 2x)

x^2 + 7x - 9 + 3x^2 - 2x + x^2 + 7x - 9 + 3x^2 - 2x

Rearranging order:

3x^2 + 3x^2 + x^2 + x^2 + 7x + 7x - 2x - 2x - 9 - 9

Combine like terms

8x^2 + 10x - 18

no, the equation would be invalid since they are both not equal.

step-by-step explanation:

here you got

4y-6+4y 2-9

first, you would simplify the equation on the form.

4y-6+4y 2-9

then, move all the terms that contains a y to the left and all the other terms to the right.

+4y-4y+-9-6

finally, you will simplify the left and the right side of the equation.

y=-3

the 4th choice is the correct one

step-by-step explanation: