What is the algebraic expression for the discriminant?
b^2-4ac
i^23
-i
sqrt(72)
sqrt(72)
sqrt(36)*sqrt(2)
6sqrt(2)
Matt is solving by factoring. What is his next step?
x^2-2x=8
x^2-2x-8=0
( )( )=0
(x-4)(x+2)=0
Julia is solving by factoring. What is her next step?
x^2=2x+35
? = 0
x^2=2x+35
x^2-2x-35=0
If the discriminant is greater than zero, are my roots real/imaginary AND are they equal/unequal?
real AND unequal
(6-i)-(22+3i)
-16-4i
sqrt(112)
sqrt(112)
sqrt(16)*sqrt(7)
4sqrt(7)
Solve:
x^2+17=0
x^2+17=0
x^2=-17
sqrt(x^2)=pmsqrt(-17)
x=pmisqrt(17)
Solve:
x^2-10=12
x^2-10=12
x^2=22
sqrt(x^2)=pmsqrt(22)
x=pmsqrt22
If the discriminant is less than zero, are my roots real/imaginary AND are they equal/unequal?
imaginary AND unequal
(4-i)(3+2i)
12+8i-3i-2i^2
12+5i-2(-1)
14+5i
sqrt(-49)-sqrt(-25)
sqrt(-49)-sqrt(-25)
7i - 5i
2i
Solve:
x^2-12x+3=-33
x^2-12x=-36
x^2-12x+(-6)^2=-36+(-6)^2
x^2-12x+36=-36+36
(x-6)(x-6)=0
x=6
Solve:
16x-61=-x^2+3
16x-61=-x^2+3
x^2+16x-64=0
x^2+16x+(8)^2=64+(8)^2
x^2+16x+64=64+64
(x+8)(x+8)=128
(x+8)^2=128
sqrt((x+8)^2)=pmsqrt(128)
x+8=pm8sqrt(2)
x=-8pm8sqrt(2)
If the discriminant is equal to zero, are my roots real/imaginary AND are they equal/unequal?
real AND equal
4x i(3i-i)^2
4x i(2i)^2
4x i(4i^2)
4x i(4(-1))
4x i(-4)
-16x i
sqrt(-44)
sqrt(-44)
sqrt(-1)*sqrt(4)*sqrt(11)
2isqrt(11)
Solve:
x^2+16x-61=0
x^2+16x-61=0
x^2+16x=61
x^2+16x+(8)^2=61+(8)^2
x^2+16x+64=125
(x+8)^2=125
sqrt((x+8)^2)=pmsqrt(125)
x+8=pm5sqrt(5)
x=-8pm5sqrt(5)
Solve:
x^2-20x+101=0
x^2-20x+101=0
x^2-20x=-101
x^2-20x+(-10)^2=-101+(-10)^2
x^2-20x+100=-101+100
(x-10)(x-10)=-1
(x-10)^2=-1
sqrt((x-10)^2)=pmsqrt(-1)
x-10=pmi
x=10pmi
James calculated the discriminant of a quadratic:
(3)^2-4(2)(-2)
Are his roots real/imaginary AND are they equal/unequal?
real AND unequal
(4-isqrt(2))(4+isqrt(2))
16+4isqrt(2)-4isqrt(2)-i^2(sqrt(2))^2
16-(-1)(2)
16+2
18
2sqrt(-175)
2sqrt(-175)
2*sqrt(-1)*sqrt(25)*sqrt(7)
2i*5sqrt(7)
10isqrt(7)
Solve:
x^2+8x+20=0
x^2+8x+20=0
x^2+8x=-20
x^2+8x+(4)^2=-20+(4)^2
x^2+8x+16=-20+16
(x+4)^2=-4
sqrt((x+4)^2)=pmsqrt(-4)
x+4=pm2i
x=-4pm2i
Solve:
x ^2 +10x+50=0
x^2 +10x+50=0
x^2+10X=-50
x^2+10x+(5)^2=-50+(5)^2
x^2+10x+25=-50+25
(x+5)^2=-25
sqrt((x+5)^2)=pmsqrt(-25)
x+5=pm5i
x=-5pm5i