Let A and B be the two complementary angles.
A = smaller angle = 2x
B = larger angle = 13x
x = some unknown number
Note how the ratio A:B turns into 2x:13x which simplifies to 2:13
A+B = 90 ... because the angles are complementary
2x+13x = 90 ... substitution
15x = 90
x = 90/15
x = 6
A = 2*x = 2*6 = 12 degrees
B = 13*x = 13*6 = 78 degrees
The two angles are 12 degrees and 78 degrees.
Check:
A/B = 12/78 = (2*6)/(13*6) = 2/13, so A:B = 2:13
A+B = 12+78 = 90
Answer:
17.690 miles
Step-by-step explanation:
i took the test
Answer:
Surface area of cylinder= 211.5π
Step-by-step explanation:
Given,
Height of cylinder = 19cm
Diameter of cylinder = 9cm
i.e Radius of cylinder = diameter/2 = 9/2 = 4.5cm
Surface area of cylinder = 2πrh + 2πr²
Plug corresponding values of r and h in surface are formula.
Surface area of cylinder = 2πrh + 2πr² = 2π*4.5*19 + 2π*4.5²
Surface area of cylinder = 171π+40.5π = 211.5π
Hence we get surface area of cylinder= 211.5π
