Answer:
Step-by-step explanation: you can use a protractor if you have 1 or seeing as the bottom left is 65, the bottom right will be the same, mostly a guess but half 65 and try that.
Answer:
8r^4
Step-by-step explanation:
√(64r^8) = √((8r^4)^2) = 8r^4
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You can make use of either or both of these rules of exponents:
(a^b)^c = a^(b·c) . . . . . used above
![\sqrt[n]{a}=a^{\frac{1}{n}}](https://tex.z-dn.net/?f=%5Csqrt%5Bn%5D%7Ba%7D%3Da%5E%7B%5Cfrac%7B1%7D%7Bn%7D%7D)
Using the second rule, you can write the expression as ...

7x-2=-23 add 2 to both sides to get 7x by itself
7x=-23+2 now add the right side
7x=-21 now divide both sides by 7
x=-21/7
x=-3