All categories

3 years ago

You need to solve a system of equations. You decide to use the elimination method. Which of these is not allowed?

Mathematics

1 answer:

Serggg [28]3 years ago

8 0

Answer:

Step-by-step explanation:

The <u>Elimination Method</u> is the method for solving a pair of linear equations which reduces one equation to one that has only a single variable.

If the coefficients of one variable are opposites, you add the equations to eliminate a variable, and then solve.
If the coefficients are not opposites, then we multiply one or both equations by a number to create opposite coefficients, and then add the equations to eliminate a variable and solve.

When multoplying the equation by a coefficient, we multiply both sides of the equation (multiplying both sides of the equation by some nonzero number does not change the solution).

So, option B is not allowed (it is not allowed to multiply only one part of equation)

You might be interested in

This is a 3 question thing! HELP!

romanna [79]

Answer:

Step-by-step explanation:

MR=2x-1. First equation

RP=9x+3 second equation

MP=MR+RP third equation

MP= 2x-1+9x+3 first equation plus second equation

MP=11x+2

MP=57

57=11x+2 replaced MP value

57-2=11x

55=11x

55/11=x

X=5

6 0

3 years ago

A school chorus has 90 sixth-grade students and 75 seventh-grade students. The music director wants to make groups of performers

Tresset [83]

Answer:

The music director can form a total of 15 groups

6 Sixth grade students per group

5 Seventh grade students per group

Step-by-step explanation:

Sixth grade students = 90

Seventh grade students = 75

Find the highest common factor of 75 and 90

90 = 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90.

75 = 1, 3, 5, 15, 25, 75

The highest common factor of 75 and 90 is 15

Therefore, the music director can form a total of 15 groups

Sixth grade students per group = 90 / 15

= 6 Sixth grade students per group

Seventh grade students per group = 75 / 15

= 5 Seventh grade students per group

3 0

3 years ago

In a certain school, students can choose whether to eat in the school’s cafeteria. A reporter working for the school’s newspaper

rosijanka [135]

Answer:

The statement that is true is B. Because students self-selected whether to eat in the cafeteria, the sampling method might be biased and the sample might not be representative of all students in the school.

Step-by-step explanation:

Because of students can decide if they eat in the cafeteria or not, the sample obtained by the reporter can be extrapolated only to the population of students that actually eat in the cafeteria, not to all students population. To make a conclusion of the degree of conformity of all students population, the poll should have been conducted in a hallway of the school (to get the opinion of all students, not only the ones that go to the cafeteria). In other way, the reporter are loosing the opinion of those students that are not happy with the new menu, and decide not going to the cafeteria.

4 0

3 years ago

A bag contains green marbles and red marbles, 36 in total. The number of green marbles is 1 more than 4 times the number of red

tatuchka [14]

Answer:

Step-by-step explanation:

Total marble = 36

Let red marbles be X

Then green marble is 4X + 1

And 4X + 1 + X = 36

5X = 36 - 1

5X = 35

X = 35/5 = 7

So, green marbles = 4X + 1

= 4(7) + 1

= 29

6 0

3 years ago

Olly drove 56 km from Liverpool to Manchester.

yawa3891 [41]

Answer:

57.073 km/h approx.

Step-by-step explanation:

Total distance from Liverpool to Sheffield

= 56 + 61 km

= 117 km

Time from Liverpool to Manchester

=56 km ÷ 70 km/h

=0.8 hours

Time from Manchester to Sheffield

=75 mins

=1.25 hours

Total time = 0.8 h + 1.25 h

= 2.05 hours

Average speed from Liverpool to Sheffield

= 117 ÷ 2.05

= 57.073 km /h

Please mark as brainliest

8 0

3 years ago