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Answer:
See below ~
Step-by-step explanation:
a) Forming the equation :
⇒ We start with a number, x
⇒ Now we double it so : 2(x) = 2x
⇒ Then we add 11 to it : 2x + (11) = 2x + 11
⇒ It is equal to 25 : 2x + 11 = 25
b) Solving the equation :
Subtract 11 from both sides :
⇒ 2x + 11 - 11 = 25 - 11
⇒ 2x = 14
Divide 2 on both sides :
⇒ 2x/2 = 14/2
⇒ x = 7
Let unknown number be x
Double it
Add eleven
You got 25
Lets solve the equation