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

Two dice are rolled. What is the probability that the sum of the top numbers on the dice is 10?
The cochlea is like a rolled up triangle which allows us to hear what part of sound? Answer: Acoustics Decibels Osculation Timbre Pitch Amplitude
HELLLLLLPPPPPPPPPPPP
An increase in pressure will cause a shift of equilibrium towards the side of the reaction with the least moles of gas. TRUE FALSE
can anyone ans this question​
an issue of a magazine contained the following statement.dropping less than two inches per mile after emerging from the​ mountains, a river drains into the ocea
What is the answer to this and why?
2cm on a map are equal to 3 kn in real life. If two points are 8 cm apart on the map how far are they in real life?
I need to know the process undertaken to find the percentages
A model of a car is available in 4 colors