Answer:
d) 16x² -56x +49
Step-by-step explanation:
The square of a binomial difference will have the form ...
(ax -b)² = a²x² -2abx +b²
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The sign of the linear term will be negative, which eliminates choices A and C.
The linear term will be double the product of the roots of the other two terms.
In choice B, the linear term has a factor of 5 that appears nowhere else, so that cannot be a perfect square.
Choice D factors as ...
16x² -56x +49 = (4x -7)² . . . . the square of a difference
Consider, pls, this option (see the attachment) of 3 steps.
Answer:
x and y are coordinates and m is slope
Begin with cos(θ) = 5/13, θ in Quadrant IV
you should distinguish the 5-12-13 right-angled triangle
and then cosØ = adjacent/hypotenuse
x = 5, r = 13 , y = -12, since Ø is in IV
and sinØ = -12/13
also tan(ϕ) = −√15 = -√15/1 = y/x and ϕ is in II,
y = √15 , x = -1
r^2 = x^2 + y^2 = 15+1 = 16
r = 4
sinϕ = √15/4 , cosϕ = -1/4
you must know that:
cos(θ − ϕ) = cosθcosϕ + sinθsinϕ
= (5/13)(-1/4) + (-12/13)(√15/4)
= -5/52 - 12√15/52
= (-5-12√15)/52
