There’s two ways to substitute, but i think you mean if you know x but don’t know y. if that is true, then yes use substitution
Answer:
1,590.7 cm^3
Step-by-step explanation:
First, separate this shape into two smaller shapes you can easily find the volume of. In this example, you can separate this figure into a cone and a half-sphere.
Find the volume of the cone using the formula: V=πr^2(h/3). The radius is 7 because 14cm is the diameter, and 17cm is the height. When you solve, you get 872.32 for the volume of this cone.
Then, find the volume of the half-sphere. The volume of a sphere can be found with the formula: V=4/3πr^3. The radius is, again, 7. Now divide this value in half because you only want to find the volume of a half-sphere. You should get 718.38 cm.
Now add the two volumes together to get 1,590.7 cubed centimeters.
Answer: Option D) 18.5 ft
Solution:
Area of the isosceles triangle: A=105 ft^2
Base of the isosceles triangle: B=12 ft
Length of each leg of the isosceles triangle: L=?
A=BH/2
Height of the isosceles triangle (perpendicular to the base): H=?
Replacing the known values in the formula of Area:
105 ft^2=(12 ft)H/2
105 ft^2=(6 ft)H
Solving for H: Dividing both sides by 6 ft:
(105 ft^2)/(6 ft)=(6 ft)H/(6 ft)
17.5 ft=H
H=17.5 ft
Using the Pytagoras Theorem:
c^2=a^2+b^2
with:
c=L=?
a=B/2=(12 ft)/2→a=6 ft
b=H→b=17.5 ft
L^2=(6 ft)^2+(17.5)^2
L^2=36 ft^2+306.25 ft^2
L^2=342.25 ft^2
sqrt(L^2)=sqrt(342.25 ft^2)
L=18.5 ft
Answer: The length of each leg is 18.5 ft
In a 30 60 90 triangle, the "middle-sized" side = the short side multiplied by the square root of 3.
so the "middle-sized" side = x * square root of 3.
Source:
http://www.1728.org/trig2.htm
