1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Artyom0805 [142]
3 years ago
13

Marcel made an error when he used the distributive property to solve the problem shown. Which sentence describes the error? In S

tep 2, 90 should be multiplied by the quantity 10 – 12, not by 10. 10 was substituted for x at the wrong step. In Step 1, the expression should be x(90 – 12) not 90(x– 12). There should be no parentheses in Step 1. It should be 90 • x – 12.
Mathematics
1 answer:
nordsb [41]3 years ago
3 0

The picture with the complete question is attached below :

Answer:

In Step 2, 90 should be multiplied by the quantity 10 – 12, not by 10

Step-by-step explanation:

90 * x - 90 * 12 = 90(x - 12)

From the question, x = 10

Hence,

90(10 - 12)

(90* 10) - (90 * 12) - - - > correct evaluation

900 - 1080

= - 180

Hence, both values in the bracket, that is 10 and - 12 should be multiplied by 90. Not just 10 alone.

You might be interested in
One diagonal of a rhombus has endpoints (-11, -9) and (-5, -3).
valina [46]

Answer:

(-10, -8) and (-6, -4)

Step-by-step explanation:

we know that

The diagonals of a rhombus are perpendicular

If two lines are perpendicular, then the product of their slopes is equal to -1

m1*m2=-1

step 1

Find the slope of the given diagonal

we have

(-11, -9) and (-5, -3)

m=(-3+9)/(-5+11)

m=-6/6=-1

Find the slope of the other diagonal

we have

m1=-1

Find m2

m1*m2=-1

(-1)*m2=-1

m2=1

step 2

Verify the slope of each of the endpoints of the other diagonal

The slope of the other diagonal must be equal to 1

so

case a) (-10, -4) and (-6, -8)

m=(-8+4)/(-6+10)

m=-4/4=-1

therefore

The points of case a) cannot be the end-points of the other diagonal

case b) (-8, -3) and (-5, -6)

m=(-6+3)/(-5+8)

m=-3/3=-1

therefore

The points of case b) cannot be the end-points of the other diagonal

case c) (-8, -4) and (-8, -8)

m=(-8+4)/(-8+8)

m=-4/0 -----> undefined

therefore

The points of case c) cannot be the end-points of the other diagonal

case d) (-10, -8) and (-6, -4)

m=(-4+8)/(-6+10)

m=4/4=1

therefore

The points of case d) can be the end-points of the other diagonal

6 0
3 years ago
HELP PLEASE!!!!!!!!!!!!!!!!!!!! I NEED IT ASAP!!!!!!!!!
FinnZ [79.3K]
I hope this helpssss

4 0
2 years ago
Read 2 more answers
Solve 2(n+2)=4n + 1 -2
Afina-wow [57]
2n + 4 = 4n - 1
5 = 2n
n = 5/2
7 0
3 years ago
A store owner estimates that by charging x dollars each for a certain lamp, he can sell 25 - x lamps each week. What price will
erma4kov [3.2K]

Answer:

\frac{25}{2} or 12.5

Step-by-step explanation:

So if 25 - x items are sold, and they each cost x, we can write an equation for the revenue to be

y = (25 - x)x

The vertex of this equation will represent the maximum revenue.  So we need to write this equation in vertex form so we can find the vertex.

Vertex from is

y = a(x - h)^2+ k,

where (h,k) represent the vertex.

the vertex form of this equation would be

y= -(x-\frac{25}{2} )^{2} +\frac{625}{4}

And the vertex would be

(\frac{25}{2} ,\frac{625}{4})

This means the maximum revenue will occur when x = 25/2

6 0
3 years ago
These is for a test.
bearhunter [10]
The discriminant is part of the quadratic formula which is b²-4ac.

So, in this case,

b²-4ac = (-9)(-9) - 4(7)(-8) = 305
7 0
3 years ago
Other questions:
  • What is 51.5% of 845 million
    7·1 answer
  • mr. Brown shares with the class that 70% of students got an A on the English vocabulary quiz if mr. Brown has a total of 100 stu
    12·2 answers
  • Milo receives a commission of 4% on all sales. If his commission on a sale was $51.00 , find the cost of the item he sold.
    5·2 answers
  • Douglas works for a racing car team.
    13·1 answer
  • Andy, Fergus, Evelyn, and Margaret are collecting cans for recycling. Before lunch they have collected a total of 173 cans. At t
    6·1 answer
  • How do i solve this
    13·2 answers
  • The movie club is having a new member sale, so Mindy signs up. The equation -0.4x + 0.05y - 1.25 = 0 relates y, the total cost,
    9·2 answers
  • In the fraction three fifths, which statement best describes the numerator?
    5·2 answers
  • There are 8 students on the school chess team. They need to raise at least $760 for a field trip. Their advisor says they still
    13·1 answer
  • Help please!!!! it makes so sense
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!