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2 years ago

Add the equations 4x−4y =-2 and −9x4y=-3

Mathematics

1 answer:

goblinko [34]2 years ago

6 0

Answer:-5x-8y=-5

Step-by-step explanation:

add right sides of equation and even them with result of adding right sides of equation

4x-4y-9x-4y=-2-3

-5x-8y=-5

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Twenty times one hundred and one (20 x 101)

Dmitrij [34]

Answer:

2020

Step-by-step explanation:

2020

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2 years ago

Which number completes the Pythagorean Triple of 9, 12, x?

Pavlova-9 [17]

The Pythagorean theorem is A^2 + B^2 = C^2. So you will do 9^2 + 12^2 = 225. The square root of 225 is 15, and so is the answer d. hope this helps

3 0

2 years ago

A positive real number is 2 less than another. When 4 times the larger is added to the square of the smaller, the result is 49.

Kobotan [32]

Answer:

The numbers are

$-2+3\sqrt{5}$ and $3\sqrt{5}$

Step-by-step explanation:

Let

x -----> the smaller positive real number

y -----> the larger positive real number

we know that

A positive real number is 2 less than another

$x=y-2$

$y=x+2$ ----> equation A

When 4 times the larger is added to the square of the smaller, the result is 49

$4y+x^2=49$ ----> equation B

substitute equation A in equation B

$4(x+2)+x^2=49$

solve for x

$x^2+4x-41=0$

The formula to solve a quadratic equation of the form

$ax^{2} +bx+c=0$

is equal to

$x=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}$

in this problem we have

$x^2+4x-41=0$

$a=1\\b=4\\c=-41$

substitute in the formula

$x=\frac{-4\pm\sqrt{4^{2}-4(1)(-41)}} {2(1)}$

$x=\frac{-4\pm\sqrt{180}} {2}$

$x=\frac{-4\pm6\sqrt{5}} {2}$

$x=-2\pm3\sqrt{5}$

The positive real number is

$x=-2+3\sqrt{5}$

Find the value of y

$y=x+2$

$y=-2+3\sqrt{5}+2$

$y=3\sqrt{5}$

6 0

3 years ago

What is 5+2? Ive been totally stuck on this for the longest time. I really need help

eduard

that's a tricky one!

but it is 7 i believe

5 0

2 years ago

What is 4.293 in expanded notation

fenix001 [56]

4 + 0.2 + 0.09 + 0.003

3 0

2 years ago