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

Understand the central concerns that motivated the antifederalists and indicate their economic and political differences with the federalists
Some irrational numbers are integers. True or false? Explain your choice.
what is the least prime number greater than 50
Is "supercalifragilisticexpialidocious" a real word or just a random phrase said in Mary Poppins?
what is the number 8.293 round in the tenths
At 10 A.M., the temperature was 71F°. At 3 P.M., the temperature was 86F°. Find the value of the slope and explain what it means.
What continent is located south of Europe
1. 8X7= 2. 9X6= 3. 6X4=
A family uses 12,986.64 Swiss francs per year to pay a mortgage that requires US dollars. Approximately how much, in US dollars, does the family spend per month
why is every number with a 5 in the ones place not prime