The answer is -3x^2+10xy+8y^2
Answer:
B) -4
Step-by-step explanation:
(5/2)x + y = 2
x + (2/3)y = 4
y = 2 - (5/2)x
x + (2/3)(2 - (5/2)x) = 4
x + 4/3 - (5/3)x = 4
(-2/3)x = 8/3
-2x = 8
x = -4
Answer:
A
Step-by-step explanation:
We know that identity:
cos^2x+sin^2x=1.
From that we have:
cos^2x=1-sin^2x.
So it is:
cos^2x-sin^x=(1-sin^2x)-sin^2x=1-2sin^2x.
And this is A).
B) is not treu because cos^2 is not sin^2x+1
C) is not true because cos^2x-sin^x=1 is false.
D) is not treu because cos^2x is not sin^2x-1
