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
IrinaK [193]
3 years ago
13

Answer this equation

Mathematics
1 answer:
Rudik [331]3 years ago
3 0

Answer:

The solution to the box is

a = 2.1

b = 5.9

c = 0.9

d = 10

Step-by-step explanation:

To answer the equation, we simply name the boxes a,b,c and d.

Such that

a + b = 8 ---- (1)

b - c = 5 ------ (2)

d * c = 9 ------ (3)

a * d = 21 ------- (4)

Make d the subject of formula in (3)

d * c = 9 ---- Divide both sides by c

d * c/c = 9/c

d = 9/c

Substitute 9/c for d in (4)

a * d = 21

a * 9/c = 21

Multiply both sides by c

a * 9/c * c = 21 * c

a * 9 = 21 * c

9a = 21c ------ (5)

Make b the subject of formula in (1)

a + b = 8

b = 8 - a

Substitute 8 - a for b in (2)

b - c = 5

8 - a - c = 5

Collect like terms

-a - c = 5 - 8

-a - c = -3

Multiply both sides by -1

-1(-a - c) = -1 * -3

a + c = 3

Make a the subject of formula

a = 3 - c

Substitute 3 - c for a in (5)

9a = 21c becomes

9(3 - c) = 21c

Open bracket

27 - 9c = 21c

Collect like terms

27 = 21c + 9c

27 = 30c

Divide both sides by 30

27/30 = 30c/30

27/30 = c

0.9 = c

c = 0.9

Recall that a = 3 - c

So, a = 3 - 0.9

a = 2.1

From (1)

a + b = 8

2.1 + b = 8

b = 8 - 2.1

b = 5.9

From (3)

d * c = 9

Substitute 0.9 for c

d * 0.9 = 9

Divide both sides by 0.9

d * 0.9/0.9 = 9/0.9

d = 9/0.9

d = 10.

Hence, the solution to the box is

a = 2.1

b = 5.9

c = 0.9

d = 10

You might be interested in
Combine to create an equivalent expression -n + (-4) - (-4n) +6
Sav [38]

Answer: The answer is 3n + 2

Step-by-step explanation: You will have to combine like terms:

=−n + −4 + 4n + 6

=(−n + 4n) + (−4 + 6)

=3n + 2

3 0
3 years ago
Please help I need for graph
Gala2k [10]
For a you will see a bar graph and the dependent o think would be bird species
3 0
2 years ago
HELPPPPPPPPP please fast
gtnhenbr [62]

Answer:

B. 1

Step-by-step explanation:

I used a calculator

5 0
3 years ago
Read 2 more answers
Find all the powers of 3 that are in the range 3 through 1000
Ksivusya [100]
So just use a calculator but here goes
3^1=3
3^2=9
3^3=27
3^4=81
3^5=243
3^6=729

and 3^7 is 2187 which is excluded











8 0
3 years ago
HELP CANT FIND ANYWHERE ON THE SITE<br> IF RIGHT ANSWER U GET CLOUT AND BRAIN
Maksim231197 [3]

Answer:

B

Step-by-step explanation:

5 0
2 years ago
Read 2 more answers
Other questions:
  • Reduce the ratio 14:63
    8·2 answers
  • Which expressions are factors of the quadratic function represented by this graph?
    7·1 answer
  • The vertical lines that intersect and form 90 degree angles<br> are called
    9·1 answer
  • Kiran says we should add the constraint 1 is greater than or less than 0
    6·1 answer
  • Find the lowest common denominator of 1/3 and 2/5
    9·1 answer
  • I’m having trouble with this answer
    11·1 answer
  • Which of the following is a direct proportion?<br> A. y=7x<br> B. y=x+7<br> C. y=7x−7<br> D. y=7
    12·1 answer
  • How do i do this question? Please help...
    11·1 answer
  • You want to buy a computer. The computer costs $1,200. How much
    11·1 answer
  • Hellp help<br>x =x=x, equals <br><br>^\circ <br><br>∘<br><br> degrees
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!