Questions: Twice the sum of -2 and a number is the same as the number decreased by 7/4. Find the number.
Transcript text: Twice the sum of -2 and a number is the same as the number decreased by $\frac{7}{4}$. Find the number.
Solution
Solution Steps
To solve the problem, we need to translate the given statement into a mathematical equation and then solve for the unknown number.
Identify the unknown number and represent it with a variable, say \( x \).
Translate "Twice the sum of -2 and a number" into an algebraic expression: \( 2(-2 + x) \).
Translate "the number decreased by \( \frac{7}{4} \)" into an algebraic expression: \( x - \frac{7}{4} \).
Set the two expressions equal to each other to form the equation: \( 2(-2 + x) = x - \frac{7}{4} \).
Solve the equation for \( x \).
Step 1: Define the Variable and Translate the Statement
Let \( x \) be the unknown number. The problem states that twice the sum of \(-2\) and the number is the same as the number decreased by \( \frac{7}{4} \).
Step 2: Form the Equation
Translate the statement into an equation:
\[
2(-2 + x) = x - \frac{7}{4}
\]
Step 3: Simplify the Equation
Simplify both sides of the equation:
\[
2(-2 + x) = 2x - 4
\]
\[
x - \frac{7}{4} = x - 1.75
\]
Step 4: Solve for \( x \)
Set the simplified expressions equal to each other and solve for \( x \):
\[
2x - 4 = x - 1.75
\]
Subtract \( x \) from both sides:
\[
x - 4 = -1.75
\]
Add 4 to both sides:
\[
x = 2.25
\]