8/15 = 56/105
This may be solved using proportion.
a/b = c/d
ad = bc where cross products are equal.
a = 8
b = f
c = 56
d = 105
ad = bc
8*105 = f*56
840 = 56f
840/56 = 56f/56
f = 15
56 ÷ 7 = 8
105 ÷ 7 = 15
Answer:
3 hours
Step-by-step explanation:
he washed one car in 20 minutes so 9 cars will be 20 x 9=180minutes which is 3 hours
Answer:
- Perimeter = 22*sqrt(2)
- Area = 60.5 inches
- D
Step-by-step explanation:
Remark
You need 2 facts.
- A square has 4 equal sides.
- It contains (by definition) 1 right angle but since we are not including and statement about parallel sides, it needs 4 right angles.
That means you can use the Pythagorean Theorem.
If one side of a square is a then the 1 after it is a as well.
Formula
- a^2 + a^2 = c^2
- 2a^2 = c^2
Givens
Solution
- 2a^2 = 11^2
- 2a^2 = 121 Divide by 2
- a^2 = 121/2 Take the square root of both sides
- sqrt(a^2) = sqr(121/2)
- a = 11/sqrt(2) Rationalize the denominator
- a = 11 * sqrt(2)/[sqrt(2) * sqrt(2)]
- a = 11 * sqrt(2) / 2
<em><u>Perimeter</u></em>
P = 4s
- P = 4*11*sqrt(2)/2
- P = 44*sqrt(2)/2
- P = 22*sqrt(2)
You don't need the area. The answer is D
<em><u>Area</u></em>
- Area = s^2
- Area = (11*sqrt(2)/2 ) ^2
- Area = 121 * 2 / 4
- Area = 60.5
