Answer:
y =-14
Step-by-step explanation:
Inverse variation is of the form
xy = k where k is a constant
(-7)(-8) = k
56 = k
The equation is
xy = 56
Let x = -4
(-4)y = 56
y = 56/-4
y =-14
Answer:
1 : 4 : 9
Step-by-step explanation:
Given the ratio of diameters = a : b , then
ratio of areas = a² : b²
Here ratio of diameters = 1 : 2 : 3 , so
ratio of areas = 1² : 2² : 3² = 1 : 4 : 9
Formula: A = pi(r)^2
1/4(2)^2pi
1/4 * 4 pi = just pi
The area would be 3.14
Answer: 
Step-by-step explanation:
Answer:
three times the sum of a number and 4, if n were to represent the unknown number, is:
3(n + 4)
18 more than a number is:
n + 18
If these two are the same, then they are equal to each other, then:
3(n + 4) = n + 18
*Do the distributive property on the left*
3n + 12 = n + 18
*Combine like terms*
2n = 6
*Divide both sides by 2*
n = 3
The number is 3.