I set it up as a ratio with hours on the top and the fraction of the job on the bottom. It looks like this: 5/(2/3) / x/1, because 1 is the whole job if 2/3 is only a fraction of it. Cross multiplying gives you 2/3x = 5. Solving for x gives you that it will take 7.5 hours to complete a whole job if it takes 5 hours to complete 2/3 of it.
Answer:
9
Step-by-step explanation:
a^2 + b^2 = h^2
15^2= 12^2 + b^2
225=144+b^2
81=b^2
9
Answer:
x equals 3 :) if i helped, please give brainliest!
Step-by-step explanation:
Answer:
A.) x-y=2 and x+2y=-2
Step-by-step explanation:
For option A, we have:
x-y=2
x+2y=-2
Subtract the first equation from the second, to get:
2y--y=-2-2
This implies that:
2y+y=-2-2
Simplify to get:
3y=-4
Divide both sides by 3 to get:
We substitute y=-1.3 into the first equation to get:
x--1.3=2
x+1.3=2
x=2-1.3
x=0.7
The solution is (0.7,-1.3), which is approximately (0.7, -1.4)
By inspection, all the other factors have solutions not close to (0.7, -1.4)
Express √3 + i in polar form:
|√3 + i| = √((√3)² + 1²) = √4 = 2
arg(√3 + i) = arctan(1/√3) = π/6
Then
√3 + i = 2 (cos(π/6) + i sin(π/6))
By DeMoivre's theorem,
(√3 + i)³ = (2 (cos(π/6) + i sin(π/6)))³
… = 2³ (cos(3 • π/6) + i sin(3 • π/6))
… = 8 (cos(π/2) + i sin(π/2))
… = 8i
