MATHEMATICS
MIDDLE SCHOOL

Answer: 20% is the answer

Hope this helps

Hope this helps

Answer:

Answer:

30 Students

Step-by-step explanation:

Suppose there are a total of 150. If you have 80% adding all the other subjects then 100% - 80% is 20%

20/100 = ?/150 cross multiply

150*20 is 3000

then 3000 divided by 100 is 30

There 30 is your answer!! Hope it helped (P.S sorry its 3 years late I just saw)

MIDDLE SCHOOL

the scale of a map 1 cm : 5km The distance between two cities is 112 km How far apart are they on a map?

Answer:

22.4 cm

Step-by-step explanation:

We can use proportions to solve. Put the distance on the map over the distance in real life.

1 cm x cm

------------ = --------------

5 km 112 km

Using cross products

1 * 112 = 5x

Divide by 5

112/5 = 5x/5

22.4 =x

Answer:

22.4 cm

Step-by-step explanation:

If 1 cm = 5 km then....

Simply divide by 5:

112 / 5 = 22.4!

:)

HIGH SCHOOL

Please help :) Solve the system of equations and choose the correct answer from the list of options.

d + e = 1

−d + e = −5

Label the ordered pair as (d, e). (4 points)

(0, 0)

(3, −2)

(−2, 3)

(−3, 0)

For a system of equations such as this, add both of the equations together. The d values will cancel each other out, making 2e=-4. This means that e=-2. If you plug this into one of the equations, you will have d + (-2) = 1. Isolate the variable by adding -2 to both sides: d=3. Written in the format described above (d,e), your answer is (3, -2).

(3, -2)

Given equations are

d+e=1

-d+e=-5

We need to find d and e.

What is system of equations?A system of equations is a set of one or more equations involving a number of variables

The system of equations are

d+e=1....(1)

-d+e=-5....(2)

d=1-e (from 1)

Substitute d in (2)

-(1-e)+e=-5

-1+e+e=-5

-1+2e=-5

2e=-5+1

2e=-4

e=-2

Now substitute value of e in (1)

d-2=1

d=1+2

d=3

Therefore the ordered pair for d + e = 1 and −d + e = −5 is (3, -2)

i.e value of d=3 and e=-2

To learn more about of system of equations click here: brainly.com/question/12895249

#SPJ2

MIDDLE SCHOOL

the sum of two numbers is 18. twice the first number increased by three times the second number equals 40. find the numbers

Answer:

4 and 14

Step-by-step explanation:

:the sum of two numbers is 18" can be written as

x + y = 18 let x represent the first number, and y the second

"twice the first number increased by three times the second number equals 40" can be written as

2x + 3y = 40

Now solve this system. Using elimination will probably be the easier method...

1. x + y = 18

2. 2x + 3y = 40

Multiply equation 1 by -2 so the x variable will be the opposite of the x variable on equation 2.

1. -2x - 2y = -36

2. 2x + 3y = 40

Now add the equations together, cancelling out 'x'

y = 4 ( 2x + (-2x) = 0, so 'x' is gone, 3y + (-2y) = y, 40 + (-36) = 4)

Since y = 4, plug that into either equation 1 or 2 and solve for x

1. x + 4 = 18 (y becomes 4)

x = 14 (subtract 4 on both sides to isolate 'x')

MIDDLE SCHOOL

Simplify the expression. What is (-8.6)^0

Answer:

1

Step-by-step explanation:

Any number to the power of zero is equal to 1. If the negative would be on the outside of the parenthesis, though, the answer would be -1