Leonard did this work to solve an equation. Did he make an error?
Leonard did not make an error.
Leonard made an error because multiplying -5 by -7 equals 35.
Leonard made an error because he should have simplified inside the parentheses first.
Leonard made an error because he should have subtracted 4x from both sides.
Leonard made an error because he should have simplified inside the parentheses first. This is essential in algebra, as operations inside parentheses take precedence over other operations. By not doing so, he may have arrived at an incorrect solution to the equation. Always remember to follow the order of operations (PEMDAS/BODMAS) when solving equations!