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

Mr.Adams drives a school bus twice a day for 5 days a week. Each trip averages 35.8 miles. In one week, how many miles has Mr.Adams driven?
Working together, Adam and Ming porch in 7.24 minutes. Had she done it alone it would have taken Ming 15 minutes. How long would it take Adam to do it alone?
why was selim’s capture of mecca, medina, and cairo so significant
which organelles store food, water, and waste material?
I really need help thank y’all
Question 1 of 25 2 Points The graph shows the change in a fish population over several years. During this same time, artificial fertilizer was used nearby Fish
Shawn has $15,000 to invest. She will put some of it into a fund that pays 4.5% annual interest and the rest in a certificate of deposit that pays 1.8% annual i
unabbreviated electron configuration of sodium
Matt can hours. One day his friend Jessica helped him and it only took 6.96 hours. Find how long it would have taken Lea 11 hours. Find how long it would take J
Graph function using the slope and y-intercept. f(x)=1/2x+2