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3 years ago

What are the solutions to 2x^2-4x-30=0

Mathematics

1 answer:

oksano4ka [1.4K]3 years ago

5 0

Answer:

ill try 2x2-4x-30=0

Two solutions were found :

x = 5

x = -3

Step by step solution :

Step 1 :

Equation at the end of step 1 :

(2x2 - 4x) - 30 = 0

You might be interested in

1/4 (dot) 3/5 simplifily

stich3 [128]

Answer: 1/20 (fraction) or 0.05 (decimal)

Step-by-step explanation:

first i like to make them a decimal so its easier.

1/4 = 0.25

1/5 = 0.2

multiply 0.25 and 0.2 = 0.05

make 0.05 a fraction

1/20

simplify. (it's already in its simplest form)

the answer is 1/20 as a fraction or 0.05 as a decimal.

(i dont know which one ur teacher wants u to do fraction or decimal?)

3 0

2 years ago

Omae wa sinderou nani (questions in the image btw)

Korvikt [17]

Let $a$ be the number of hours worked at Job A and $b$ the number of hours at Job B. Then

$a+b=30$

and

$7.5a+8b=234.50$

From the first equation,

$b=30-a$

and substituting this into the second gives

$7.5a+8(30-a)=234.50\implies-0.5a+240=234.50$

$\implies0.5a=5.50$

$\implies\boxed{a=11}$

5 0

3 years ago

Help me please!!!!!!!!!!

kompoz [17]

Answer:

do 15.05/7 mutiply that by 3 that is your awnser

Step-by-step explanation:

6 0

2 years ago

For positive acute angles A and B, it is known that cos A= 20/29 and tan B= 11/60. Find the value of cos(A + B) in simplest form

jek_recluse [69]

Answer:

$\displaystyle \cos(A + B) =\frac{969}{1769}$

Step-by-step explanation:

We are given that:

$\displaystyle \cos A=\frac{20}{29}\text{ and } \tan B=\frac{11}{60}$

Where A and B are positive acute angles.

And we want to find cos(A + B).

Recall that cosine is the ratio of the adjacent side to the hypotenuse. Using this information, find the opposite side with respect to Angle A:

$o=\sqrt{29^2-20^2}=21$

Tangent is the ratio of the opposite side to the adjacent side. Find the hypotenuse with respect to Angle B:

$h=\sqrt{11^2+60^2}=61$

In summary:

With respect to Angle A, the adjacent side is 20, opposite is 21, and the hypotenuse is 29.

With respect to Angle B, the adjacent side is 60, the opposite is 11, and the hypotenuse is 61.

We can rewrite our expression as:

$\displaystyle \cos(A+B)=\cos A\cos B-\sin A\sin B$

Using the above information, substitute in the appropriate values. Note that since A and B are positive acute angles, all trigonometric values will be positive. Hence:

$\displaystyle \cos(A + B)=\left(\frac{20}{29}\right)\left(\frac{60}{61}\right)-\left(\frac{21}{29}\right)\left(\frac{11}{61}\right)$

Simplify:

$\displaystyle \cos(A + B) =\frac{1200-231}{1769}=\frac{969}{1769}$

3 0

2 years ago

If I got a 35% out of 20 questions and Im going to get half credit in the 13 problems I got wrong what is going to be my percent

dsp73

Answer:

Step-by-step explanation:

So since each question is 5% (100/20=5)

we can do ((13*5)/2) because of half credit we divide by two

now we get 32.5% back

32.5%+35%=67.5%

unless of course of extra points on other assignments, the highest grade you can get in that class (if every other thing is a 100%) is an 87 if im not mistaken.

7 0

3 years ago