Solve. show all work, I'll give u a best. √ √?

Question

. 3x^2 - 10 x + 15 = 0

so whats the complex roots

thx all 4 hlp me ...

Answer 1

3x^2 - 10 x + 15 = 0

Use the quadratic formula:
[-b +/- sqrt(b^2 - 4ac)] / 2a
= [10 +/- sqrt(100 - 4*3*15)] / 2*3
= [10 +/- sqrt(100 - 180)] / 6
= [10 +/- sqrt(-80)] / 6

So there is no real solution since you are taking the square root of a negative number, but you can find the complex roots:

[10 +/- sqrt(-80)] / 6
= [10 +/- 4*sqrt(-5)] / 6
= [5 +/- 2*sqrt(-5)] / 3
= [5 +/- 2i*sqrt(5)] / 3

Answer 2

Hey there!

I thought I had answered this question. Guess you have deleted it. I'll solve the equation again, by completing the square.

3x^2-10x+15=0 -->
3x^2-10x=-15 -->
x^2-(10/3)x=-5 -->
x^2-(10/3)x+(10/6)^2=-5+(10/6)^2 -->
x^2-(10/3)x+(5/3)^2=-5+(5/3)^2 -->
(x-5/3)^2=(-45/9)+(25/9) -->
(x-5/3)^2=-20/9 -->
x-5/3=±sqrt(-20/9) -->
x-5/3=±sqrt(-20)/sqrt(9) -->
x-5/3=±2isqrt(5)/3 -->
x=5/3±2isqrt(5)/3 -->
x=(5±2isqrt(5))/3

So the answer is x=(5±2isqrt(5))/3 or x is approximately equal to 1.67±1.49.

Hope it helps!

Answer 3

This is a simple quadratic polynomial in the form:

ax^2 + bx + c

where a=0.3, b=-10, c=15

To find the roots of this equation, use the quadratic equation:

[-b +- sqrt(b^2 - 4ac)] / 2a

[10 +- sqrt(100 - (4)(0.3)(15))] / (0.3)(2)

[10 +- sqrt(100-18)] / 0.6

[10 +- sqrt(82)] / 0.6

So, there are two roots of the equation:

[10 + sqrt(82)] / 0.6 and [10 - sqrt(82)] / 0.6

The square root of 82 is about 9.05538514, so the two roots are

31.7589752 and 1.5743581

Thus, that equation is true when x is either 31.7589752 or 1.5743581.

Answer 4

Standard form: ax^2 + bx + c = 0
3x^2 - 10x + 15 = 0
where
a = 3, b = -10, c = 15

By the Quadratic formula,

x = [ -(-10) + or- sqrt( (-10)^2 - 4(3)(15) ] / [ 2(3) ]

x = [ 10 +or- sqrt(-80) ] / 6

note: sqrt(-80) = sqrt(16)sqrt(-1)sqrt(5) = 4i*srqt(5)

x = [ 10 +or- 4i*sqrt(5) ] / 6

x = 2[ 5 +or- 2i*sqrt(5) ] / (2*3)

x = [ 5 + 2i*sqrt(5) ] / 3 or x = [ 5 - 2i*sqrt(5) ] / 3

Answer: x = { [ 5 + 2i*sqrt(5) ] / 3, x = [ 5 - 2i*sqrt(5) ] / 3 }

Answer 5

3x² - 10x + 15 = 0
x = [ 10 ± √ (- 80) ] / 6
x = [ 10 ± 4√5 i ] / 6
x = [ 5 ± 2√5 i ] / 3

Answer 6

3x^2 - 10 x + 15 = 0
Use the quadratic formula
x= [-(-10) +/- sqrt((-10)^2-4(3)(15))]/(2*3)
x = [10 +/- sqrt(100 - 180)]/6
x = [10 +/- sqrt(-80)]/6
x = [10 +/- 4sqrt(5)i]/6
x = 5/3 +/- (2i/3)*sqrt(5)

Answer 7

Kyle and Ironduke appear correct. If you just copy their solution into your homework you'll get the answer right, but you won't learn it so you'll miss the same question on the test (when it counts). So follow what they did and re-work it by hand yourself.

Answer 8

3x^2-10x+15=0
-15 -15
3x^2-10x=-15
I don't know what the ^ symbol means so I can't do the rest.

Answer 9

no real root babe.....dont try to fool around i know even u that well dont u...?!1