Question

Solve: 9x^2 - 16x + 60 + 0

Answer 1

Quadratic formula?

Answer 2

Seems difficult to factor mentally.

Answer 3

Yet agian

Answer 4

In your previous post you mentioned you were asked to find the discriminant first. Is this the same question?

Answer 5

Kinda But i really just need the answer or to have it explaned to where i get the answer because its been 8 hours i have been working on this test.

Answer 6

I would rather it be explained.

Answer 7

\[\Large x = \frac{ -b \pm \sqrt{b ^{2} - 4ac} }{ 2a } = \frac{ -(-16) \pm \sqrt{(-16) ^{2} - 4(9)(60)} }{ 2(9) } \]

Answer 8

whoa

Answer 9

\[x = \frac{ -b \pm \sqrt{b ^{2} - 4ac} }{ 2a } = \frac{ -(-16) \pm \sqrt{(-16) ^{2} - 4(9)(60)} }{ 2(9) }\]

Answer 10

Is that the quadratic formula?

Answer 11

Yes, that is the quadratic formula. Use your calculator and simplify the right hand side.

Answer 12

ok one second than

Answer 13

@Luigi0210 it seems difficult to factor mentally because it is irreducible :-)

Answer 14

ok

Answer 15

I got some crazy numbers

Answer 16

16 √ 256 - 2,160 / 18 right?

Answer 17

Mr @ranga did i do it correctly?

Answer 18

\[\frac{ 16 \pm \sqrt{256-2160} }{ 18 } = \frac{ 16 \pm \sqrt{-1904} }{ 18 }\]

Answer 19

Simplify further. There is a negative inside the square root. So this is a complex number. square root of -1 is "i". Also write 1904 as 119 * 16. square root of 16 is 4 which can be pulled out of the square root along with "i".

Answer 20

-43.63 correct

Answer 21

\[\frac{ 16 \pm \sqrt{-1904} }{ 18 } = \frac{ 16 \pm \sqrt{-1 * 16 * 119} }{ 18 } = \frac{ 16 \pm 4i\sqrt{119} }{ 18 }\]

Answer 22

could this just be 16-43.63/18 and 16 + 43.63/18 and simplyfy

Answer 23

\[= \frac{ 8 \pm 2i\sqrt{119} }{ 9 }\]

Answer 24

Unless they want the answer in decimal, leave it as a fraction.
\[x = \frac{ 8 }{9} + \frac{2i\sqrt{119} }{ 9 }~~or~~x = \frac{ 8 }{9} - \frac{2i\sqrt{119} }{ 9 }\]

Answer 25

Well is algebra 1? would it be a decimal?

Answer 26

Usually in math we leave it as fractions. In Science and Engineering applications we may resort to decimals.

Answer 27

But follow what your instructor says or see some class room examples.

Answer 28

oh. ok. It seems when i have done this before i could leave it a fraction. P.S forgot everything.

Answer 29

Yes, the "symbolic" form is much better than writing down decimals — often you can't even write the exact answer as a decimal! This would be one of those cases.

Answer 30

Usually easy to crank out a number if you need it, but much harder to go from a number to an expression.

Answer 31

So that is the answer above. If you want you cam factor out 2/9 and write the answer as: \[x = \frac{ 2 }{9} (4 + i\sqrt{119})~~or~~x = \frac{ 2 }{9} (4 - i\sqrt{119})\]

Answer 32

thats for the Fraction answer.?

Answer 33

Ok thank you i have like 5 of these to do and this will help.

Answer 34

Alright. And good luck. Apply the quadratic formula and be careful when simplifying.

Answer 35

And yes, I meant "symbolic" and fractional form as whpalmer4 mentioned. The symbol here being the square root symbol. The fractional part is 2/9. 119 is not a perfect square and so the square root of 119 will be an irrational number. Rather than using the calculator to find square root of 119 we leave it in the symbolic form sqrt(119). Also we leave the fraction 2/9 as it is instead of concerting it into an approximate decimal.