Domik weights 30 pounds more than his sister
Together they weigh 330 pounds
Let "x" represent the weight of Dominik's sister, then his weight can be expressed as "x+30"
And their total weight can be calculated as:

From this expression you can calculate the value of x:

x=150 pounds
x+30=150+30=180 pounds
Dominik weights 180pounds and his sister 150 pounds
Answer
Well first you need to remove parentheses by multiplying factors. Next
use exponent rules to remove parentheses in terms with exponents. Then
combine like terms by adding coefficients. Finally you just
combine the constants.
a^4+2a+8 because if you combine like terms that is what you get
Richard is 14 years old and Teo is 6 years old.
Step-by-step explanation:
Let,
Richard's age = x
Teo's age = y
Combined age = 20 years
According to given statement;
x+y=20 Eqn 1
x = 2y+2 Eqn 2
Putting value of x from Eqn 2 in Eqn 1

Dividing both sides by 3

Putting y=6 in Eqn 2

Richard is 14 years old and Teo is 6 years old.
Keywords: linear equation, substitution method
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