Use the quadratic formula
x2 + 2x - 15
Complete the square
x2 - 3x - 10
x = 5, x = -2
x = -2, x = -3
Factor
4x2 - 4x - 3
(2x + 1)(2x - 3)
so x = -1/2 or x = 3/2
Write down the quadratic formula
[-b +/- sqrt(b2 - 4ac)]/2a
Use the quadratic formula
x2 -15x + 56
x=7 or x=8
Complete the square
x2 + 6x + 9
x = -3
Factor
x2 - 12x + 27
x = 9, x = 3
Solve for x if
log3(81) = x
3x = 81
so x = 4
Solve for x if
2x2 + 14x + 24 = 0
2x2 + 14x + 24 = 0
2(x2 + 7x + 12) =
2(x+3)(x+4) = 0
x = -3 or x = -4
Use the quadratic formula
2x2 + 3x + 4
[-3 +/- sqrt(-23)]/4
Complete the square
x2 - x - 8.75
x = 3.5, x = -2.5
Factor
x2 - 7x - 30
x=10, x= -3
Solve for x if
log2(16) = x
so x = 4
Solve for x if
log10(x) = 3
so
x = 1,000
Use the quadratic formula
x2 + 8x + 9
Complete the square
x2 - 3x + 2
x = 1, x = 2
Factor
x2 - 2x - 35
x = -5, x = 7
Factor
6x2 - 1x - 7
(6x - 7)(x + 1)
so x = 7/6 or x = -1
Compute the sum:
1 + 2 + 3 + ... + 48 + 49 + 50
1 + 2 + 3 + ... + 48 + 49 + 50 =
50(51)/2 = 25*51 = 1,275
Use the quadratic formula
x2 - x + 1
Complete the square
x2 + 2x - 63
x = 7, x = -9
Factor
x2 - 12x + 32
x = 4, x = 8
Compute the sum
3 + 6 + 9 + ... + 297 + 300
3 + 6 + 9 + ... + 297 + 300 =
3 ( 1 + 2 + 3 + ... + 99 + 100) =
3 (100)(101)/2 = 15,150
Factor
6x2 - 60x + 126
6x2 - 60x + 126 =
6(x2 - 10x + 21)
6(x - 3)(x - 7)
so x = 3 or x = 7