Ask question

Ask question

All categories

3 years ago

9

Use elimination to solve this system of equations x-4y=11 5x-7y=-10

1 answer:

attashe74 [19]3 years ago

8 0

First, isolate x in x-4y=11 because 1 is x's coefficient.
x-4y=11
x=11+4y
Now, substitute 4y+11 for x in 5x-7y=-10.
5x-7y=-10
5(4y+11)-7y=-10
20y+55-7y=-10
Add all coefficients.
13y+55=-10
Isolate y by subtracting 55 from both sides.
13y+55=-10
13y=-10-55
13y=-65
y=-5
Now substitute -5 for y in your first equation.
x=11+4y
x=11+4(-5)
x=11-20
x=-9
Your answer would be (-9,-5).
Any questions you may have, please contact me or comment.

You might be interested in

A surveying team set up some equipment 104104 ft from the base of a tree in order to sight the top of the tree. From ground leve

jarptica [38.1K]

Answer:

Relative error = 0.0254 %

Step-by-step explanation:

Given details

Height of equipment from base is 104 ft

Elevation angle is 27.5 degree

From figure we have

$tan\theta = \frac{x}{104}$ .........1

$tan(27.5) = \frac{x}{104}$

x = 54.13 ft

differentiating 1st eq wrt x

$\frac{d}{dx} tan\theta = \frac{d}{dx} [\frac{x}{104}]$

$sec^2\theta \frac{d\theta}{dx} = \frac{1}{104}$

Taken $d\theta \ as \Delta x \ and\ dx = \Delta x$ for minute change

$\Delta x = 1.5% x$

$= 0.015 \times 54.13 = 0.8119 ft$

from $sec^2 \theta \frac{d\theta}{dx} = \frac{1}{104}$

$\Delta \theta = \frac{1}{104 sec^2 \theta} \Delta x$

$\Delta \theta = \frac{1}{104 \times 1.115} 0.8119$

$\Delta \theta = 0.007$

Reltaive error $= \frac{\Delta \theta}{\theta} \times 100$

$= \frac{0.007}{27.5}\times 100$

Relative error = 0.0254 %

4 0

4 years ago

Help i will give brainliest

Gre4nikov [31]

The answer is the last one (-5x7)!

4 0

3 years ago

Read 2 more answers

6th grade math! Question 8 (:

Naddik [55]

Answer:

B. 120

Step-by-step explanation:

Each ribbon is 25 yards long. Each yard is 36 inches, so the length of the ribbon is ...

(25 yd)(36 in/yd) = 900 in

This can be divided into n pieces, where n satisfies ...

22n ≤ 900

n ≤ 900/22 = 40 20/22

That is, Erika can cut 40 22-inch pieces from each 25-yard piece, and will have 20 inches left over.

From the 3 25-yard pieces, Erica can cut 3×40 = 120 pieces of ribbon that are 22 inches long.

_____

She will have 3 pieces that are 20 inches left over.

3 0

4 years ago

Find 5 rational numbers between -3/4 and 5/6

insens350 [35]

Answer:

1/2, 1/3, 1/4, 1/5, 1/6

Step-by-step explanation:

6 0

3 years ago

Gina and Derek saw some trees on their walk through the park. They made a diagram showing the distance between trees. Please see

lara31 [8.8K]

Answer:

B. 9 yards

Step-by-step explanation:

you just have to add the oak to pine and pine to end then you subtract the total of maple to end.

8 0

2 years ago