She made the mistake of grouping unlike terms and factorizing.
Given that
Helene is finding the sum (9 + 10i) + (–8 + 11i).
She rewrites the sum as (–8 + 11)i + (9 + 10)i.
We have to determine
Which statement explains the property of addition that she made an error in using?
According to the question
The mistake she did is in the second term distributing.
(9+10i) is not equal to (9+10)i
Similarly (-8+11i) is not equal to (-8+11)i.
The correct method she should have done is given below;
Grouping real terms together and imaginary terms together and finding the sum is,
Hence, she made the mistake of grouping unlike terms and factorizing.
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brainly.com/question/10078818
Answer:
4515
Step-by-step explanation:
Answer: 
Step-by-step explanation:
Step 1:-
Given equations are y=-2 x+30........(1)
another equation is y=4 x ..........(2)
Step 2:-
solving these two equations (1) and (2)
Equating both equations are 
Step 3:-
The final answer is
Answer:
2x - y - 7 = 0
Step-by-step explanation:
Since the slope of parallel line are same.
So, we can easily use formula,
y - y₁ = m ( x ₋ x₁)
where, (x₁, y₁) = (8, 9)
and m is a slope of line passing through (x₁, y₁).
and since the slope of parallel lines are same, so here we use slope of parallel line for calculation.
and, Slope = m = 
here, (xₐ, yₐ) = (2, 7)
and, 
⇒ m = 
⇒ m = 2
Putting all values above formula. We get,
y - 9 = 2 ( x ₋ 8)
⇒ y - 9 = 2x - 16
⇒ 2x - y - 7 = 0
which is required equation.
= 9a(5x² + 3x + 2)
The distributive property lets you remove the same factor from all terms and write it outside parentheses.
