All categories

3 years ago

Solving x + 3y = 5 and -x - y = -3 by eliminationg.

Mathematics

1 answer:

Marina CMI [18]3 years ago

4 0

Answer:

(x, y) = (2, 1)

Step-by-step explanation:

The x-coefficients are opposites of each other, so the x variable will be eliminated if the two equations are added.

(x +3y) +(-x -y) = (5) +(-3)

2y = 2

y = 1

Substituting into the first equation gives ...

x +3(1) = 5

x = 2 . . . . . . . subtract 3

The solution is (x, y) = (2, 1).

You might be interested in

Conti. 7-10 thanks a lot! unhelpful answers will be deleted.

Marysya12 [62]

Answers:

10. b. $\displaystyle 13$

9. b. $\displaystyle 20$

8. a. $\displaystyle 33$

7. a. $\displaystyle 25°$

Step-by-step explanations:

10. Both segments are considered congruent, so turn both expressions into an equation:

$\displaystyle 3x - 5 = x + 7 \hookrightarrow \frac{-12}{-2} = \frac{-2x}{-2} \\ \\ 6 = x$

Plug this back into the equation to get $\displaystyle 13$ on both sides.

9. All edges in a square obtain congruent right angles and edges, so set $\displaystyle 45$ equivalent to the given expression:

$\displaystyle 45 = 2x + 5 \hookrightarrow \frac{40}{2} = \frac{2x}{2} \\ \\ \boxed{20 = x}$

8. Both angles are considered supplementary, so turn both expressions into an equation and set it to one hundred eighty degrees:

$\displaystyle 180 = (4x - 15)° + (x + 30)° \hookrightarrow 180° = (15 + 5x)° \hookrightarrow \frac{165}{5} = \frac{5x}{5} \\ \\ \boxed{33 = x}$

7. In this rectangle, segment EO is a segment bisectour, making these angles Complementary Angles. Therefore, set an equation up to find its complement:

$\displaystyle 90° = 65° + m\angle{VOE} \\ \\ \boxed{25° = m\angle{VOE}}$

I am joyous to assist you at any time.

3 0

2 years ago

The product od 2 and y is at least 10

alexgriva [62]

Hello There!

It could be represented by this:
$xy \geq 10$

Hope This Helps You!
Good Luck :)

- Hannah ❤

8 0

3 years ago

Which is f(5) for the function -2x2 + 2x - 3?

Schach [20]

The value of f(5) is -37

Solution:

Given function is:

$f(x) = -2x^2+2x+3$

We have to find the value of f(5)

To find the value of f(5), we have to substitute x is equal to 5 in given function

Plug in x = 5 in f(x)

$f(x) = -2x^2+2x+3\\\\f(5) = -2(5)^2+2(5) + 3\\\\\text{Simplify the above expression }\\\\f(5) = -2(25) + 10 + 3\\\\\text{Solve the above expression }\\\\f(5) = -50 + 10 + 3\\\\f(5) = -40 + 3 = -37$

Thus value of f(5) is -37

6 0

3 years ago

A semi circle has a radius 8.2 cm

zaharov [31]

Answer:

Step-by-step explanation:

$Area=\frac{1}{2}*\pi *r^{2}\\\\=\frac{1}{2}*3.14*8.2*8.2\\\\=3.14*4.1*8.2\\$

= 105.57

= 105.6 cm²

5 0

3 years ago

Read 2 more answers

A local hamburger shop sold a combined total of 445 hamburgers and cheeseburgers on Tuesday. There were 55 fewer cheeseburgers s

liberstina [14]

Let x represent the number of hamburgers sold, and (x - 55) represent the number of cheeseburgers sold.

Set up an equation:
hamburgers + cheeseburgers = total number of burgers

x + (x-55) = 445

solve for x:
2x - 55 = 445

2x = 445 + 55

2x = 500

x = 500÷2

x = 250

This means 250 hamburgers were sold on Tuesday.

Hope this helps!

-Jabba

4 0

3 years ago