Use substitution
From second equation:-
x = 13 - 5y, Substitute for x in the first eqaution:
(13 - 5y)^2 + y^2 = 13
169 -130y + 25y^2 + y^2 - 13 = 0
26y^2 - 130y + 156 = 0
26(y^2 - 5y + 6) = 0
26(y - 3)(y - 2) = 0
y = 2 , y = 3
From the second equation when y = 2, x = 13 - 5(2) = 3
and when y = 3, x = 13 - 5(3) = -2
So the solution is [3, 2} and {-2, 3}
This equals one and one eighth
Answer:
-8√6
or
-19.59
Step-by-step explanation:
B. is the only one we know for sure. We know that when we put in -2 we get exactly one answer or output.
This is what you're looking for if I'm not mistaken
sin²x + cos²x = 1
So:
sin²x = 1 - cos²x
∴ sin²x * cos²x = (1 - cos²x) * cos²x
= cos²x.(1 - cos²x)
(= cos²x - cos⁴x)