13.
(a)
for x = 2:
for x = 5
(b)
The graph is:
(c)
Using the graph:
Using the quadratic formula:
![\begin{gathered} x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a} \\ x=\frac{-21\pm\sqrt[]{21^2-4(-5)(-10)}}{2(-5)} \\ x=\frac{-21\pm\sqrt[]{241}}{-10} \\ x=0.54758 \\ or \\ x=3.6524 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20x%3D%5Cfrac%7B-b%5Cpm%5Csqrt%5B%5D%7Bb%5E2-4ac%7D%7D%7B2a%7D%20%5C%5C%20x%3D%5Cfrac%7B-21%5Cpm%5Csqrt%5B%5D%7B21%5E2-4%28-5%29%28-10%29%7D%7D%7B2%28-5%29%7D%20%5C%5C%20x%3D%5Cfrac%7B-21%5Cpm%5Csqrt%5B%5D%7B241%7D%7D%7B-10%7D%20%5C%5C%20x%3D0.54758%20%5C%5C%20or%20%5C%5C%20x%3D3.6524%20%5Cend%7Bgathered%7D)
The answer would be letter b
Follow PEMDAS.
You would first do your distributive property which is, -5(z+2). You would multiply -5 to z and -5 to 2 which will give you -5z + -10.
so now you have 2z-5z+ -10= -8 - 2z. Now you must isolate the variable. So subtract -8 to -10 which will give you -18.
Now you have the equation 2z-5z-18=-2z
Now combine like terms. 2z-5z= -3z
Now you have the equation -3z-18=-2z
Now you must move the -3z to the other side of the equal sign by adding the opposite which is +3z to -2z which will give you +1z
Now you have -18= 1z
Now you divide. -18 divided by 1 is -18.
So your final answer will be -18=z
