The truck in this example is 14 feet tall if it's shadow is 12 feet long.
The total R value is computed from the R-values of the components in the stack as ...
(inches of wood)*(R-value of wood) +(inches of fiberglass)*(R-value of fiberglass) +(inches of foam)*(R-value of foam)
= (4 in)(2 /in) +(2 in)(4 /in) +(3 in)(5 /in)
= 8 +8 +15
= 31
The total R-value of the wall is 31.
Answer:
c = 20 inches
Step-by-step explanation:
To find the sides of a right triangle, you use the Pythagorean Theorem.
a² + b² = c²
You know a and b, and you need to find c, the hypotenuse.
Plug in a and b.
(12)² + (16)² = c²
Simplify by solving the exponents.
144 + 256 = c²
Combine the constants.
400 = c²
Take the square root of both sides.
√400 = √c²
Solve the √
±20 = c
The length cannot be negative, so you can eliminate that as an option.
So, c = 20