Answer :
Answer:
Let the first equation be x + y = 10
x = 10 -y
2nd equation will be 1x + 1.2y = 11
Substituting in 2nd equation
(10 - y) + 1.2y = 11
10 - y + 1.2y = 11
.2y = 1
y = 5
If y = 5, x = 5: coz x + y = 10
She have buy 5 stamps of each $1 stamps and 5 stamps of each $1.20 stamps.
What is a linear equation?
A linear equation is an equation that has the variable of the highest power of 1.
The standard form of a linear equation is of the form Ax + B = 0.
Let the first equation be;
x + y = 10
x = 10 -y
2nd equation will be,
1x + 1.2y = 11
Substituting in 2nd equation;
(10 - y) + 1.2y = 11
10 - y + 1.2y = 11
0.2y = 1
y = 5
If y = 5, x = 5:
x + y = 10
Hence, She have buy 5 stamps of each $1 stamps and 5 stamps of
each $1.20 stamps.
Learn more about linear equations;
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