Answer:
a
Step-by-step explanation:
Put x = -2 and y = 5 to the expression.
![\left[3\cdot(-2)^3(5)^{-2}\right]^2=\left[3(-8)\cdot\dfrac{1}{5^2}\right]^2=\left(-24\cdot\dfrac{1}{25}\right)^2=\left(-\dfrac{24}{25}\right)^2\\\\=\dfrac{24^2}{25^2}=\dfrac{576}{625}](https://tex.z-dn.net/?f=%5Cleft%5B3%5Ccdot%28-2%29%5E3%285%29%5E%7B-2%7D%5Cright%5D%5E2%3D%5Cleft%5B3%28-8%29%5Ccdot%5Cdfrac%7B1%7D%7B5%5E2%7D%5Cright%5D%5E2%3D%5Cleft%28-24%5Ccdot%5Cdfrac%7B1%7D%7B25%7D%5Cright%29%5E2%3D%5Cleft%28-%5Cdfrac%7B24%7D%7B25%7D%5Cright%29%5E2%5C%5C%5C%5C%3D%5Cdfrac%7B24%5E2%7D%7B25%5E2%7D%3D%5Cdfrac%7B576%7D%7B625%7D)
explanation
Before we begin, note the following:
+ve * +ve = +ve
-ve * -ve = +ve
+ve * -ve = -ve
-ve * +ve = -ve
Now, for the given question:
The given equation is:
78 = -2(m+3) + m
To solve for m, we need to isolate m on one side of the equation and compute its value as follows:
78 = -2(m+3) + m
78 = -2m - 6 + m
m-2m = 78+6
-m = 84
m = 84/-1
m = -84
