Question

II. PROBLEM SOLVING: Solve the following problem and show your complete solution
1. If A varies directly as t² and A=100 when t=5 find
a. an equation connecting A and t,
b. the value of A when t=√7
2. It is given that y+1 varies directly as x. If y=11 when x=4, find a. an equation connecting x and y, b. the value of y when x=7
c. the value of x when y=5x
3. If (W-2) varies inversely as x³ and W=5/2 when x=4
a. an equation connecting x and W
b. the value of W when x=1/2
4. It is given that y varies inversely as x². If x is decreased by 50%, find the percentage change in y.
5. If Q varies jointly as x and y, and Q=120 when x=3 and y=8, find
a. an equation connecting x,y, and Q
b. the value of Q when x=5 and y=12
6. If P varies directly as u² and inversely as v, P=832 when u=16 and v=4, find
a. an equation connecting P, u, and v,
b. the value of v when P=637 and u=28.
7. Simplify (a^3/2 b^2/3 ÷a²)³

Answer 1

Answer:

A=k.t^2 where k is a constant. This is the equation

A=100, t=5

put these values in the above equation

100=k.5^2=25k

k=100/25=4

The value of A when t=√7 is

A=4×(√7)^2=4×7=28