The pattern is:
( a - b )² = a² - 2 a b + b² ( square of last term of binomial - the missing term)
x² - 2 · 8 · x + 8² = x² - 16 x + 64 = ( x - 8 )²
The missing term is: 64
x+6 is x+6. It's an expression. Not sure what you need help with.
4x+1+57=90
4x+58=90
4x=32
X=8
First you would have to find the base which would be 9^2 + 9^2= C^2 because of the pythagorean theorem. So the base would equal 12.7. To find the area of a triangle it’s A= h•b / 2. So your answer would be 95.25