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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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For what value of x is the rational expression below equal to zero x-4/(x+5)(x-1)

Tanzania [10]

We have that

<span>(x-4)/(x+5)(x-1)
</span> the rational expression is equal to zero <span>whenever its numerator is zero
</span>x-4=0---------> x=4

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3 years ago

Yertle the turtle and his 362 turtle buddies went swimming in 3 different ponds. if the same number of turtles swim in each pond

konstantin123 [22]

There are 363 turtles (including yertle)
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2 years ago

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zubka84 [21]

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3 years ago

Suppose that an individual has a body fat percentage of 14.5% and weighs 171 pounds. How many pounds of his weight is made up of

scZoUnD [109]

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3 years ago

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Setler [38]

Answer:

=0.3 per km²

Step-by-step explanation:

Population density is the population per uni area.

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2 years ago