Try this option:
if x+y=-9 is I (one)
and x+2y=-25 is II (two), then
if II-I, then (x+2y)-(x+y)=-25+9 ⇔ y=-16.
Answer:
26.8°
Step-by-step explanation:
The cosine of an angle is the ratio of the adjacent side of the triangle in which the angle is formed to the hypotenuses side of the triangle. The cosine of the angle gives the ratio of these sides. However, the arc cosine of the ratio gives the angle measured in degrees.
If cos B = 0.8926
then arc cosine 0.8926 which may be expressed as cos-1 0.8926 will give the value of B.
B = cos-1 0.8926
= 26.8°
<h3>E
xplanation:</h3>
Replace cos^2(θ) with 1-sin^2(θ), and cot(θ) with cos(θ)/sin(θ).
cos^2(θ)cot^2(θ) = cot^2(θ) - cos^2(θ)
(1 -sin^2(θ))cot^2(θ) = . . . . . replace cos^2 with 1-sin^2
cot^2(θ) -sin^2(θ)·cos^2(θ)/sin^2(θ) = . . . . . replace cot with cos/sin
cot^2(θ) -cos^2(θ) = cot^2(θ) -cos^2(θ) . . . as desired
Answer: 82% decrease
Step-by-step explanation:
Initial number =5000
Final number = 900
Change in numbers = 5000 - 900 = 4100
Since 5000 > 900 ( the change is a decrease)
Thus, the percent change =
(4100/5000) x 100%
= 82%
Thus, the percent of change from 5,000 to 900 is 82% decrease