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3 years ago

7x+3y=22 4y=20 I need to know how to write this equation out with the answer

Mathematics

2 answers:

xeze [42]3 years ago

5 0

7x+3y=22
4y=20

4y=20
y=5

Substitute to first equation
7x+15=22
7x=7
x=1

WITCHER [35]3 years ago

3 0

$\begin{cases} 7x+3y=22 \\ 4y=20 \ \ /:4 \end{cases}\\ \\\begin{cases} 7x+3 \cdot 5=22 \\ y= 5 \end{cases}\\ \\\begin{cases} 7x+15=22 \ \ |-15 \\ 4y=20 \end{cases}$

$\begin{cases} 7x+15 -15=22 -15 \\ y=5 \end{cases}\\ \\\begin{cases} 7x =7\ \ / :7 \\ y=5 \end{cases}\\ \\\begin{cases} x =1 \\ y=5 \end{cases}\\ \\$

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3 years ago

Sven got a $150 gift card function A(n) 150 12.30n gives the amount of money left on the gift card after n number of visits to t

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Answers:

1. The n-intercept is 12. That means after 12 visits the amount of money on the gift car is $0.

2. The A(n)-intercept is 150. Before the visits, the amount of money on the gift car is $150.

Solution:

Amount of money on the gift card after n number of visits: A(n)=$150-$12.50 n

A(n)=150-12.50 n

1. n-intercept

A(n)=0→150-12.50 n =0

Solving for n: Subtracting 150 both sides of the equation:

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Dividing both sides of the equation by -12.50:

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3 years ago

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Answer:

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Step-by-step explanation:

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