Solve the following system of equations

x = 4

y = 8

Step-by-step explanation:

From the question given above,

3.2x – 0.6y = 8 (1)

–0.8x + 0.9y = 4 (2)

We shall determine the value of x and y by using elimination method as illustrated below:

3.2x – 0.6y = 8 (1)

–0.8x + 0.9y = 4 (2)

Multiply equation 1 by 0.8 and equation 2 by 3.2

0.8 × (3.2x – 0.6y = 8)

2.56x – 0.48y = 6.4 (3)

3.2 × (–0.8x + 0.9y = 4)

–2.56x + 2.88y = 12.8 (4)

Next, add equation 3 and 4 together. This is illustrated below:

2.56x – 0.48y = 6.4

+ –2.56x + 2.88y = 12.8

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2.4y = 19.2

Divide both side by 2.4

y = 19.2 / 2.4

y = 8

Substitute the value of y into any of the equation to obtain the value of x. Here, we shall use equation equation 1. This is illustrated below:

3.2x – 0.6y = 8

y = 8

3.2x – 0.6(8) = 8

3.2x – 4.8 = 8

Collect like terms

3.2x = 8 + 4.8

3.2x = 12.8

Divide both side by 3.2

x = 12.8 / 3.2

x = 4

From the calculations made above,

x = 4

y = 8

a) justify

step-by-step explanation:

justifying is just part of everyday life. justify kind of means proof so i think the answer is a) justify.

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step-by-step explanation: