Identify the rate of change

Sherina wrote and solved the equation. x-56=230 x-56-56=230-56 x=174 what was sherina’s error? sherina’s work is correct. sherina only needed to subtract 56 from 230. sherina made a subtraction error when subtracting 56 from 230. sherina should have added 56 to both sides of the equation.

Cot(90° − x) = 1 the value of x that satisfies this equation is °. a. 60 b. 135 c. 225 d. 315

Christina can paint 420 square feet in 105 minutes. which unit rate describes the scenario?