Question
Solve the quadratic equation
Solve using the quadratic formula
Solve by completing the square
Solve using the PQ formula
x1=415−357,x2=415+357
Alternative Form
x1≈−1.912376,x2≈9.412376
Evaluate
2x2−15x−36=0
Substitute a=2,b=−15 and c=−36 into the quadratic formula x=2a−b±b2−4ac
x=2×215±(−15)2−4×2(−36)
Simplify the expression
x=415±(−15)2−4×2(−36)
Simplify the expression
More Steps

Evaluate
(−15)2−4×2(−36)
Multiply
More Steps

Multiply the terms
4×2(−36)
Rewrite the expression
−4×2×36
Multiply the terms
−288
(−15)2−(−288)
Rewrite the expression
152−(−288)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
152+288
Evaluate the power
225+288
Add the numbers
513
x=415±513
Simplify the radical expression
More Steps

Evaluate
513
Write the expression as a product where the root of one of the factors can be evaluated
9×57
Write the number in exponential form with the base of 3
32×57
The root of a product is equal to the product of the roots of each factor
32×57
Reduce the index of the radical and exponent with 2
357
x=415±357
Separate the equation into 2 possible cases
x=415+357x=415−357
Solution
x1=415−357,x2=415+357
Alternative Form
x1≈−1.912376,x2≈9.412376
Show Solution
