Equations can be used to find the number of pencils (x) and pens (y) she bought are X+1.5Y = 21, and X+Y = 18
The correct option is C.
One or two variables make up a linear equation. Neither the numerator nor the denominator of a fraction can be a variable in a linear equation raised to a power higher than 1. The lines that connect all the points on a coordinate grid when you identify the values that make a linear equation true are congruent.
Let x stand for the number of pencils Stella purchased, and y for the number of pens Stella purchased.
Since Stella purchased a total of 18 things, the quantity of pencils and pens purchased must equal 18 or one of the following:
x + y = 18
We also know she spent $21, that a pencil costs $1, and that a pen costs $1.50. Therefore,
1x + 1.5y = 21
Thus, the set of equations that may be utilized to determine the quantity of pencils (x) and pens (y) that she purchased is as follows:
X+1.5Y = 21, and X+Y = 18
equations can be used to find the number of pencils (x) and pens (y) she bought are X+1.5Y = 21, and X+Y = 18
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