Answer:
D the answer is D, thats when cos and sin are equal together
Answer:
<em>never </em>because they are continually increasing at the same rate without multiplying and dividing
Answer:
(4,-3)
Step-by-step explanation:
Multiplying the bottom equation by -6, we get -6x+12y=-60.
Adding this to the first equation gives 15y=-45, and thus y=-3.
So, it follows that 6x+3(-3)=15, and thus x=4.
Answer:
Second option: 81y^4 - 16x^2, the difference of squares
Step-by-step explanation:
(9y^2-4x)(9y^2+4x) is a special product named difference of squares, then we can apply this formula:
(a-b)(a+b)=a^2-b^2, with a=9y^2 and b=4x, then:
(9y^2-4x)(9y^2+4x)=(9y^2)^2 - (4x)^2
(9y^2-4x)(9y^2+4x)=(9)^2 (y^2)^2 - (4)^2 (x)^2
(9y^2-4x)(9y^2+4x)=81y^(2*2) - 16x^2
(9y^2-4x)(9y^2+4x)=81y^4 - 16x^2