Answer:
x = - 
Step-by-step explanation:
Multiply through by 4 to clear the fraction
15 - 28x = 36 ( subtract 15 from both sides )
- 28x = 21 ( divide both sides by - 28 )
x =
= - 
Answer:
27 years old
Step-by-step explanation:
Let Alvin's age be x and Elga's age is y:
y - x = 15
x + y = 27
2y = 42 (use elimination method)
y = 21
x = 6 (plug it back into either equation)
Therefore Alvin is 6 and Elga is 27
Answer:
39 + 2x
Step-by-step explanation:
32 is the answer and it is adding 5 everytime
Take the sqrt of both sides of <span>(x+2)^2=10:
x+2 = plus or minus sqrt(10)
Solve for x: x = -2 plus or minus sqrt(10)
Evaluate x: x = -2 + sqrt(10) AND x = -2 - sqrt(10) (answers)
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