Evaluate: (-20\div(-5)) \times (10\div10-8)+7^2

Expression: $\left( -20\div\left( -5 \right) \right) \times \left( 10\div10-8 \right)+{7}^{2}$

Divide the numbers

$4\left( 10\div10-8 \right)+{7}^{2}$

Any expression divided by itself equals $1$

$4\left( 1-8 \right)+{7}^{2}$

Evaluate the power

$4\left( 1-8 \right)+49$

Calculate the difference

$4 \times \left( -7 \right)+49$

Multiply the numbers

$-28+49$

Calculate the sum

$21$