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3 years ago

30 POINTS NEED HELP

Mathematics

1 answer:

KatRina [158]3 years ago

5 0

a. The expression y=5x represent the number of small marbles she has.

b. The expression z=3x+2 represents the number of large marbles she has.

c. Amy has 310 small marbles, 62 medium marbles and 188 large marbles.

Step-by-step explanation:

a. Let x represent the number of medium marbles Amy has. Write an algebraic expression to represent the number of small marbles she has.

Medium marbles = x

Let,

Small marbles = y

According to given statement;

She has five times as many small marbles as medium marbles.

y = 5x Eqn 1

The expression y=5x represent the number of small marbles she has.

b. Write an algebraic expression to represent the number of large marbles she has.

Let,

Large marbles = z

The number of large marbles is two more than three times the number of medium marbles.

z = 3x+2 Eqn 2

The expression z=3x+2 represents the number of large marbles she has.

c. If Amy has a total of 560 marbles, how many of each size does she have?

x+y+z= 560 Eqn 3

Putting value of y and z from Eqn 1 and 2 in Eqn 3

$x+(5x)+(3x+2)=560\\x+5x+3x+2=560\\9x=560-2\\9x=558$

Dividing both sides by 9

$\frac{9x}{9}=\frac{558}{9}\\x=62$

Putting x=62 in Eqn 1

$y=5(62)\\y=310$

Putting x=62 in Eqn 2

$z=3(62)+2\\z=186+2\\z=188$

Amy has 310 small marbles, 62 medium marbles and 188 large marbles.

Keywords: linear equation, substitution method

Learn more about substitution method at:

#LearnwithBrainly

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Step-by-step explanation:

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