a very fast way to do it:
Trivially 8.8*5>10, so the power of 10 is 6+2+1 = 9.
Therefore, the answer is 
You can do:
16 - 10 and then + 1 (thats 7)
9+ ? is 16 ? ( 7)
Answer:
Step-by-step explanation:
y - 9 = -2(x - 1)
y - 9 = -2x + 2
y = -2x + 11
Y = f(3f - 4g + 3) +7g(3f - 4g + 3)
= 3f^2 - 4fg + 3f + 21fg - 28g^2 + 21g
= 3f^2 + 3f + 17fg + 21g - 28g^2