Respuesta :
Answer:
x = 6
Step-by-step explanation:
2x+9=21
Step one: 2x=21
-9
2x=12
Step two: x= 12÷2
x= 6
First step is subtract 9 on both sides to solve the given equation.
What is an equation?
An equation is a mathematical statement with an 'equal to' symbol between two expressions that have equal values. For example, 3x + 5 = 15.
Given equation
2x + 9 = 21
First step is subtract 9 on both sides
⇒ 2x + 9 - 9 = 21 - 9
⇒ 2x = 12
Second step is divide the equation with 2 on both sides
⇒ [tex]\frac{2x}{2} =\frac{12}{2}[/tex]
⇒ x = 6
Hence, First step is subtract 9 on both sides to solve the given equation.
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