Answer:
225
Step-by-step explanation:
Mary = 3x (3 times Carey)
Carey = x
Barry = x/2 (Because Carey read twice as many as Barry, it means he read half the amount Carey did)
3x + x + x/2 = 405
4x + x/2 = 405
8x/2 + x/2 (treat these as fractions) = 405
9x/2 = 405
9x = 810 (cross multiply)
x = 90
Mary = 3(90) 270
Carey = 90
Barry = 90/2 45
Mary - Barry
270 - 45 = 225
Hope this helps! :)
I am not for sure how to do this just yet when I figher it out I will try to help you.<span />
Answer:
(5x + 7y)² = 25x² + 70xy + 49y²
Step-by-step explanation:
(5x + 7y)² = 25x² + 70xy + 49y²
Because,
(5x + b)² = (5x)² + 2(5x)(b) + b²
2(5x)(b) = 70xy
b = 7y
b² = (7y)² = 49y²
Answer:
x = 40
Step-by-step explanation:
50 + 150 + 2x + x + x
200 + 4x
360 - 200 = 160
160 / 4 = 40
x = 40
50 + 80 + 40 + 150 + 40
Answer:
lateral surface area of a pyramid= 1/2pl or pl/2