All categories

3 years ago

Solve the system by substitution. 5x+2y= 5 y=-2x + 3

1 answer:

3 0

5x+2(-2x+3)=5
5x-4x+6=5
x=-1

Then plug back into either to solve for y.

y=-2(-1)+3
y=2+3
y=5

Substitution means you just replace one variable with the other equation so only one variable is showing. That’s how you solve for the first variable.

You might be interested in

The length of a rectangle is four times its width. If the area of the rectangle is 324m^2, find its perimeter.

Anuta_ua [19.1K]

Answer:

$perimeter=90$

Step-by-step explanation:

We know that the length is four times the width, so:

$l=4w$

We also know the area, which is 324 m². The formula for area:

$A=l*w$

Insert the known values:

$324=(4w)*w$

Solve for w. Simplify by removing parentheses:

$324=4w*w\\324=4w^2$

Divide 4 from both sides to isolate the variable:

$\frac{324}{4}=\frac{4w^2}{4} \\\\81=w^2$

Find the square root of both sides:

$\sqrt{81} =\sqrt{w^2} \\\\w=9$

The width is 9 m.

We know the width. Now find the length by using the area formula and inserting known values:

$324=l*9$

Solve for l. Divide both sides by 9:

$\frac{324}{9}=\frac{l*9}{9}\\\\ l=36$

The length of the rectangle is 36. (You can check: 4 times 9 is 36)

Now find the perimeter:

$P=2l+2w$

Insert values:

$P=2(36)+2(9)\\\\P=72+18\\\\P=90$

The perimeter is 90 m.

5 0

3 years ago

On the second day of a hiking trip, the tourists covered 17% bigger distance than on the first day. By how many percent did thei

finlep [7]

Speed=distance/time
suppose the distance of the first day is d, and the time is t
distance of the second day: d+0.17d=1.17d
time of the second day: t+0.2t=1.2t
speed of the second day: 1.17d/1.2t=0.975(d/t)=(1-0.025)(d/t)
so the speed of the second day is 2.5% slower than the first day.

6 0

3 years ago

Read 2 more answers

The circumference of a tennis ball is 21<br>cm. How many inches is the circumference?

Arturiano [62]

Answer:

8.26772

Step-by-step explanation:

1 centimeter is equaled to 0.393701 in inches so multiply it by 21

3 0

3 years ago

Read 2 more answers