All categories

3 years ago

Solve for x and y (use elimination or substitution). Show work.

Mathematics

2 answers:

Olenka [21]3 years ago

8 0

Yap this is the answer

mihalych1998 [28]3 years ago

5 0

7x+3y-1 = 10x -7y+9 as vertical angles

7x+3y-1 + x = 180 as supplementary angles

So, we have system of equations:

7x+3y-1 = 10x -7y+9 (1)

7x+3y-1 + x = 180 (2)

1) Simplify equation (1)

7x+3y-1 = 10x -7y+9 -----> -3x +10y =10

2) Simplify equation (2)

7x+3y-1 + x = 180 -----> 8x +3y = 181

(-3x +10y =10)*8 ------> -24x+80y =80

( 8x +3y = 181)*3 ---------> 24x + 9y = 543

-24x+80y =80

+24x + 9y = 543

89y = 623

y = 7

5) -3x +10y =10

-3x + 10*7 =10

-3x +70 =10

-3x = -60

x=20

Answer : x=20, y = 7

You might be interested in

Rewrite the expression $6j^2 - 4j 12$ in the form $c(j p)^2 q$, where $c$, $p$, and $q$ are constants. What is $\frac{q}{p}$

solniwko [45]

$Rewrite the expression 6j^2 - 4j + 12$ in the form $c(j + p)^2 + q$, where $c$, $p$, and $q$ are constants. What is $\frac{q}{p}$$

The ratio of $\frac{q}{p}$ = - 34

How to solve such questions?

Such Questions can be easily solved just by some Algebraic manipulations and simplifications. We just try to make our expression in the form which question asks us. This is the best method to solve such questions as it will definitely lead us to correct answers. One such method is completing the square method.

Completing the square is a method that is used for converting a quadratic expression of the form $ax^{2} + bx + c$ to the vertex form

$a(x - h)^{2} + k$ . The most common application of completing the square is in solving a quadratic equation. This can be done by rearranging the expression obtained after completing the square: $a(x + m)^{2} + n$ , such that the left side is a perfect square trinomial

$6j^2 - 4j +12$

= $6(j^2 - \frac{2}{3} j )+12$

= $$6(j^2 - \frac{2}{3} j + \frac{1}{9} )+\frac{102}{9}$ (Completing Square method)

= $6( j- \frac{1}{3} )^{2} + \frac{34}{3}$

On comparing with the given equation we get

p = - $\frac{1}{3}$ and q = $\frac{34}{3}$

∴ $\frac{q}{p}$ = $\frac{\frac{34}{3} }{\frac{-1}{3} }$

= - 34

Learn more about completing the square method here :

brainly.com/question/26107616

#SPJ4

7 0

2 years ago

How do you do (2/3) (-4) (9)

DochEvi [55]

Answer:

Since 3 is evenly divided by 9, we can multiply just one term to get a common denominator. Multiply 2 by 3, and get 6, then we multiply 3 by 3 and get 9.

Step-by-step explanation:

7 0

3 years ago

NEED RN, WORTH 20! What is the value of x?

max2010maxim [7]

Answer:

$x = 5.625$

Step-by-step explanation:

Step 1: Make an expression

$\frac{3}{4} = \frac{x}{7.5}$

Step 2: Cross Multiply

$\frac{3}{4} = \frac{x}{7.5}$

$4 * x = 7.5 * 3$

$4x = 22.5$

Step 3: Divide both sides by 4

$4x / 4 = 22.5 / 4$

$x = 5.625$

Answer: $x = 5.625$

5 0

3 years ago

Which of equation represents a function? A. x2 + y2 = 9 B. {(4, 2), (4, –2), (9, 3), (9, –3)} C. x = 4. 2x + y = 5

Ipatiy [6.2K]

The answer to your questions is B. {(4, 2), (4, –2), (9, 3), (9, –3)} because you don't have a repeat of a number the X side which is your output. I hope that this is the answer that you were looking for and it has helped you.

3 0

3 years ago

Please answer will give the point thing

Vlad [161]

Pizzas cost $8 and sandwiches cost $2.50

7 0

3 years ago