pre-algebra

[kanman]

Describe the possible values of x if the are of the rectangle is at least 40 square inches the rectangle has a width of 4 the length is 5/8x + 5

My answer which was wrong was 4/1(5/8x)= 5/2 x 2/5 8/1 x 2/5 = 16 in x is greater than or equal to 16

 

[Deleted member 4993]

Describe the possible values of x if the are of the rectangle is at least 40 square inches the rectangle has a width of 4 the length is 5/8x + 5

My answer which was wrong was 4/1(5/8x)= 5/2 x 2/5 8/1 x 2/5 = 16 in x is greater than or equal to 16

\(\displaystyle 4 * (\frac{5x}{8} + 5) \ge 40\)

\(\displaystyle 20x/8 + 20 \ge 40\)

\(\displaystyle 5x/2 \ge 20\)

\(\displaystyle 5x/2 * (2/5) \ge 20*2/5\)

\(\displaystyle x \ge 8\)