X2 - 16, is the answer. The first one.
x^2 - 16 = (x)^2 - 4^2, difference of two squares :)
#9. There are 180 degrees in a triangle. We already know two of the sides which added together make 112. Then we do, 180-112=68
#10. We do the same process. 90 + 60 = 150
150-180= 30
#11. To find whether or not any three numbers can make a triangle, two of the numbers must equal more than the remaining number. But this has to be the case for any combination. 6+7=13. 13 is larger than 11. So yes it can.
#12. 8+2=10 which may be bigger than 6 but, 6+2=8. Which is equal to 8. So no, it cannot make a triangle.
I’m still working out the first question
<u> 12x³ - 12x </u><u /> = 3/7 - 1/56x² - 3/7 = 3/7 - 3/7 - 1/56x² = -1/56x²
28x³ - 56x² + 28x
Answer:
Missing constant: 100
Step-by-step explanation:
perfect square (a - b)^2 = a^2 - 2ab + b^2
In this case
20x = 2 * x * 10
and
10^2 = 100
so
(x - 10)^2 = x^2 - 20x + 100
36 because NQ is 18 and the tic mark means that each half is equal to each other, and 18+18=36 :D