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3 years ago

4x + y = 73x + 2y = 9

Mathematics

1 answer:

Diano4ka-milaya [45]3 years ago

3 0

Answer:

x = 1

y = 3

Step-by-step explanation:

<h2>Substitution Method:</h2>

Step 1:

Name The Equation

4x + y = 7 ...(1)

3x + 2y = 9 ...(2)

Step 2:

From Equation (1) we get,

4x = 7 - y

i.e.,

x = 7 - y/4

Step 3:

Substitute the value of x = 7 - y/4 in equation (2)

i.e.,

3(7 - y/4) + 2y = 9

21 - 3y/4 + 2y = 9

21 - 3y + 8y/4 = 9

21 - 3y + 8y = 9 * 4

21 + 5y = 36

5y = 36 - 21

5y = 15

y = 15/5

y = 3

Step 4:

Substitute the value of y = 3 in equation (1)

4x + y = 7

i.e.,

4x + (3) = 7

4x + 3 = 7

4x = 7 - 4

4x = 4

x = 4/4

x = 1

<h2>Verification: </h2>

4x + y = 7 i.e., 4(1) + (3) = 7

3x + 2y = 9 i.e., 3(1) + 2(3) = 9

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So we can say that;

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2 years ago

4x + y = 73x + 2y = 9​

4x + y = 73x + 2y = 9