Five more than twice a number is at least 45. What is the minimum value of the number?

Question

Can't figure this out! Please help!

Answer 1

Because we have the term "at least", we set up an inequality.

2x + 5 ≥ 45

 

 

Solve the inequality for x.

 

Subtract 5 on both sides of the inequality.

 

2x ≥ 40

 

 

Divide both sides of the inequality by 2.

 

x ≥ 20

 

This solution can interpreted as all values of x greater that or equal to 20. This also means that the minimum value is 20.

Answer 2

2N+5≥45 so that 2N≥40 or N≥20