historyman historyman
  • 01-03-2017
  • Mathematics
contestada

If a + 3b = 13 and a + b = 5, the value of b is?

A. 1
B. 4.5
C. 7
D. 4

Respuesta :

AnimeBrainly
AnimeBrainly AnimeBrainly
  • 01-03-2017
the value of b is 4

a=1

1+3(4)=13
1+4=5

Answer Link
awsomejaguar
awsomejaguar awsomejaguar
  • 01-03-2017
Ans: D
First, multiply a+b=5 by 3 to make it 3a+3b=15
Second, subtract this equation from a+3b=13 to give 2a=2
Therefore, a=1
Substitute this into a+3b=13, to give 1+3b=13
So, 3b=12
Divide this 3b=12 by 3 to get for.
Therefore, b=4
Answer Link

Otras preguntas

add together 1.5m 1250mm 125cm 1.230m
draw a model to write 30/4 as mixed number
Click an item in the list or group of pictures at the bottom of the problem and, holding the button down, drag it into the correct position in the answer box. R
A grand jury consists of twelve citizens. a. True b. False
what are all the degrese an acute angle can have
If the house was less expensive, we would be able to buy it. Which change corrects the sentence? Change was to were. Change was to was not. Change would to woul
If people's ancestors were apes then why aren't we. Apes would have just kept on mating,so where did people get apes from. Also if we were all from apes the
Which text from "Helen Grey" explicitly states a consequence of Helen's behavior? (4 points)
paulo has 128 glass beads to use to decorate picture frames. He wants to use the same number of beads on each frame. If he decorates 8 picture frames, how many
What did most people do for a living in ancient China