Question

a rectangle has a length if x + 7 centimeters. The perimeter of the rectangle is 23 centimeter. What is the value of x

Answer 1

$23 = 14 + 2x$
$reasoning \: for \: each \: term \: in \: the \\ \: above \: equation\\ \\ p = 23 \\ 14 = 7 \times 2 \\ 2x = 2 \times x$
$\: \: \: \: \: 23 - 14 \: \: \: \: \: \: \: \: \: \: \: \: \: \: 14 + 2x - 14 \\ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: 9 = 2x$
$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: 9 \div 2 \: \: \: \: \: \: \: \: \: 2x \div 2 \\ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: 4.5 = x$
So, the answer is 4.5