$4x^2+12x-7=0\\\\a=4;\ b=12;\ c=-7\\\Delta=b^2-4ac\\\\\Delta=12^2-4\cdot4\cdot(-7)=144+112=256 \ \textgreater \ 0\\\\therefore\\x_1=\dfrac{-b-\sqrt\Delta}{2a}\ and\ x_2=\dfrac{-b+\sqrt\Delta}{2a}\\\\\sqrt\Delta=\sqrt{256}=16\\\\x_1=\dfrac{-12-16}{2\cdot4}=\dfrac{-28}{8}=\boxed{-\dfrac{7}{2}}\\\\x_2=\dfrac{-12+16}{2\cdot4}=\dfrac{4}{8}=\boxed{\dfrac{1}{2}}$

3 0

3 years ago

Can I please have help?

jok3333 [9.3K]

Answer:

(-3, 3) and (8, -8)

Step-by-step explanation:

having the rule (x + 3, y – 5) and an input point (x,y) you just plu th iput point into the rule and you will get the output point.

With an input point (-6,8) you plug -6 in for x and 8 in for y into the rule.

(x + 3, y – 5)

(-6 + 3, 8 - 5)

(-3, 3)

Now we do the same for (5, -3) as the input

(x + 3, y – 5)

(5 + 3, -3 - 5)

(8, -8)

4 0

3 years ago

In a batch of 890 calculators, 12 were found to be defective. What is the probability that a calculator chosen at random will be

scoray [572]

Answer:

When entered into a calculator, 12/890 (the chance of a given calculator being defective) = 0.01348...

As a percent this is 100*0.01348% = 1.348%, and to the nearest tenth, 1.3%

3 0

3 years ago

Read 2 more answers

If the variance is 81 grams, what is the standard deviation four times?

Svetlanka [38]

Answer:

102

Step-by-step explanation:

i guess

6 0

2 years ago