Answer A and Answer D along with the ones you picked beforehand
Answer: He is not correct.
Steps:
Let x1 and x2 be the first and second number, respectively.
In words, if the second is 125%, or 5/4 of the first number (first equation),
then the first is 4/5 of the second, which is 0.8 or 80%.
Answer:
c
Step-by-step explanation:
0.25r-0.125+0.5r=0.5r
0.75r-0.125=0.5r
-0.125= -0.25r
r=0.5
Pi/4 radians
You're looking for the angle that has a secant of sqrt(2). And since the secant is simply the reciprocal of the cosine, let's take a look at that.
sqrt(2) = 1/x
x*sqrt(2) = 1
x = 1/sqrt(2)
Let's multiply both numerator and denominator by sqrt(2), so
x = sqrt(2)/2
And the value sqrt(2)/2 should be immediately obvious to you as a trig identity. Namely, that's the cosine of a 45 degree angle. Now for the issue of how to actually give you your answer. There's no need for decimals to express 45 degrees, so that caveat in the question doesn't make any sense unless you're measuring angles in radians. So let's convert 45 degrees to radians. A full circle has 360 degrees, or 2*pi radians. So:
45 * (2*pi)/360 = 90*pi/360 = pi/4
So your answer is pi/4 radians.
