Answer:
The correct answer is 31x + 0.5
Step-by-step explanation:
∵ 13x + 5 + 17x - 4.5 + x
To solve this correctly you must to add the coefficients of the like terms (terms who has same variables or constant terms)
∵ 13x , 17x , x are like terms ⇒ terms with same variable
(same letters and same power)
∵ 5 , 4.5 are like terms ⇒ constant terms (numbers only)
∴ (13x + 17x + x) + (5 - 4.5) = 31x + 0.5
* <u>The error of first answer:</u>
- 18x + 17x - 4.5 + x
- She add 13x + 5 = 18x ⇒ she add unlike terms
* <u>The error of second answer:</u>
- 35x - 4.5 + x
- She add 13x + 5 + 17x = 35x ⇒ she add 2 like terms with 1 unlike term
* <u>The error of third answer:</u>
- 30.5x + x
- She add 13x + 5 + 17x - 4.5 = (13x + 17x) + (5 - 4.5) =
30x + 0.5 ⇒ she add 2 like terms and 2 constant terms
and then add the 2 unlike answers
* <u>The error of fourth answer:</u>
- 31.5x
- She add 13x + 5 + 17x - 4.5 + x = (13x + 17x + x) + (5 - 4.5) =
31x + 0.5 ⇒ she add 3 like terms and 2 constant terms
and then add the 2 unlike answers
(by quadratic formula)
, since we're taking the positive solution.