A number is 9 more than another number. Twice the sum of the two numbers is 10. Find the two numbers.

Mathematics

2 answers:

Artemon [7]3 years ago

7 0

Answer:

7, -2

Step-by-step explanation:

we call the first number "X" and the second one "Y"

X is 9 more than Y! which means we need to add 9 to Y so it'll be equal to X. so: Y+9=X

also 2×(X+Y)=10

you can also write this down as: 2X+2Y=10

now we have:

X=Y+9

2X+2Y=10

you can now put what equals to X in the second Equation:

2(Y+9)+2Y=10 => 2Y+18+2Y=10 => 4Y=10-18 =>Y= -2

the only thing left to do is to put Y= -2 in the first equation:

X= -2+9 => X=7

erik [133]3 years ago

5 0

Answer:

a = 7

b = - 2

Step-by-step explanation:

a = b + 9

2(a + b) = 10 => a + b = 5

replace a

(b + 9) + b = 5

2b = 5 - 9

2b = - 4

b = - 2

replace b

a = - 2 + 9

a = 7

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Which angles are supplementary to each other?

Rus_ich [418]

Answer:

Angle 4 and Angle 1 are supplementary to each other.

Step-by-step explanation:

A line is 180°. Because angle 4 and angle 1 and right next to each other and they share a straight line, both of their angles should add up to 180°, making these two angles supplementary.

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6 0

2 years ago

Evaluate.

lys-0071 [83]

Answer:

361/900

Step-by-step explanation:

$\left(-\dfrac{1}{6}+0.6\left(-\dfrac{1}{3}\right)+1\right)^2=\left(-\dfrac{1}{6}-0.2+1\right)^2\\\\=\left(1-\left(\dfrac{1}{6}+\dfrac{1}{5}\right)\right)^2=\left(1-\dfrac{5+6}{6\cdot5}\right)^2=\left(\dfrac{19}{30}\right)^2=\boxed{\dfrac{361}{900}}$