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3 years ago

Determine the value of a + b in the system of equations below. 5a + 4b = 22 7a-b= 11

Mathematics

1 answer:

dexar [7]3 years ago

6 0

Answer:

We have a + b as;

2 + 3 = 5

Step-by-step explanation:

Here, we want go get the value of a and b

from the second equation, we can get an expression for b

We have this as;

7a - b = 11

Thus,

b = 7a - 11

Now, from here, we can substitute the value of b into the first equation

We have this as;

5a + 4(7a - 11) = 22

5a + 28a -44 = 22

33a = 22 + 44

33a = 66

a = 66/33

a = 2

Recall;

b = 7a - 11

substituting the value of a from above;

b = 7(2) - 11

b = 14 - 11

b = 3

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3 years ago

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We are given with ;

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Multiplying both sides by 10 ;

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Can be further written as ;

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Transposing 6y to LHS and 150 to RHS

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