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3 years ago

9x-2y=-21 2x+3y=16 Substitution

1 answer:

hjlf3 years ago

3 0

$9x-2y=-21 \\\\ 9x=-21+2y \\\\ => \boxed{x=\frac{2y-21}{9}} \\\\ 2x+3y=16 \\\\ 2*\frac{2y-21}{9}+3y^{(9}=16^{(9} \\\\ 2(2y-21)+27y=144 \\\\ 4y-42+27y=144 \\\\ 31y=144+42 \\\\ 31y=186 \\\\ \boxed{y=\frac{186}{31}=6} \\\\ x=\frac{2*6-21}{9} \\\\ x=\frac{12-21}{9} \\\\ x=\frac{-9}{9} \\\\ \boxed{x=-1}$

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What's the word name for 20,004? A. Two thousand four B. Two hundred thousand four C. Twenty thousand four D. Twenty thousand fo

Vika [28.1K]

Answer:

Step-by-step explanation:

8 0

3 years ago

a store sells grass seed in small bags and large bags.the small bags have 7 pounds of seed for 27.93 and large bags cost 66.98.w

Nonamiya [84]

Answer

Find out the ratio of price to pound for each bag.

To prove

As given

A store sells grass seed in small bags and large bags.the small bags have 7 pounds of seed for $27.93 .

7 pound = $27.93

Now find out the cost for the 1 pound.

$1\ pound\ cost= \frac{27.93}{7}$

1 pound cost = $3.99

As given large bags cost $66.98.

Now find out pounds in the large bags.

Let us assume that the number of pounds in the large bags be x.

Than

3.99 × x = 66.98

$x = \frac{66.98}{3.99}$

x = 16.8 pounds (approx)

Now find out the ratio of price to pound for each bag.

As small bags weight = 7 pounds

Cost of the small bags = $27.93

$\frac{Price\ of\ small\ bag}{Cost\ of\ the\ small\ bags} = \frac{27.93}{7}$

As large bags weight = 16.8 pounds

Cost of the large bags = $66.98

$\frac{Price\ of\ large\ bag}{Cost\ of\ the\ large\ bags} = \frac{66.98}{16.8}$

Hence proved

7 0

3 years ago

NO LINKS AND PLEASE MAKE YOUR ANSWER SIMPLE.

Ber [7]

The student with the correct answer is Dylan who says the decimal should be placed between the 8 and 0.

This is base on the estimation that 3.01 is a two decimal place number, so the product 18.06 should also be in 2 decimal place.

<h3>How to find product of decimal number?</h3>

A decimal number is a number expressed in the decimal system (base 10).

Place value:

Ten thousand
Thousand
Hundred
Ten
ones
. decimal point
tenth
hundredths
thousandth
ten thousandth
hundred thousandth

6 × 3.01

3.01

3 = ones
. = decimal point
0 = tenth
1 = hundredth

6 × 3.01

= 18.06

Therefore, Lucas is incorrect with his answer that the decimal should be placed between the 1 and 8.