ACT Math Formulas| Questions and Answers with complete solution

Distance Formula - d=√(x₁-x₂)² + (y₁-y₂)² (EX: Find distance between (5,6) and (1,3) √(5-1)² + (6-3)²= √(4)² + (3)²= √16 + 9= √25= 5=Distance Slope - Slope= Rise/Run=Change in Y/Change in X (y₂-y₁/x₁-x₂) (EX: Find slope of (5,6) and (1,3) 6-3/5-(-1)= 3/6= 1/2 Slope Intercept - y=mx+b Ex: y=2/3x + 5 Midpoint Formula - (x₁+x₂)/2, (y₁+y₂)/2 PEDMAS - Parenthesis, Exponents, Multiplication, Division, Add, Subtract. EX: 9-2 x (5-3)² + 6÷3= 9-2 x (2)² + 6÷3= 9-2 x (4) +6÷3= 9-8 +2= 9-6=3 Quadratic Equation - ax²+bx+c= 0 EX: x²+ 9x+ 18=0 Quadratic Formula - ²x = −b ± √b²-4ac/2a EX: Solve using quadratic formula x²+ 9x+ 18=0: x= −9±√(9)² − 4(1)(18)/2(1) −9 ± √81 − 72/2 −9 ± √9/2 −9 ± √3/2 = -9 + 3/2 and -9 -3/2 -9+3/2= -3 and -9-3/2= -6 Percent Formula - Part=Percent x Whole