Answer:
10
Step-by-step explanation:
By the geometric mean theorem,
- 4/a = a/25
- 100=a² (cross multiply)
- a=10 (square root both sides and take the positive solution)
It is A. x = 2√3, y = 4√3
7x + 6y = 21 ⇒ 7x + 6y = 21
1x + 3y = -12 ⇒ 2x + 6y = -24
5x = 45
5 5
x = 9
x + 3y = -12
9 + 3y = -12
- 9 - 9
3y = -21
3 3
y = -7
(x, y) = (9, -7)
Answer: =−36x−54
Step-by-step explanation:
=(9)(−4x+−6)
=(9)(−4x)+(9)(−6)