Solve
2a + b = 3
4a - 5b = 20
My attempt
Multiply the first equation by 5
So,
10a + 5b = 15
4a - 5b = 20
Add them together
14a = 35
Divide both sides by 14
a = 2.5
Substitute (I have done it with the second one)
10 - 5b = 20
Take away 10 from both sides
5b = 10
Divide both sides by 5
b = 2
When I checked if the answers were right by fitting them back into the equation it didn't work
Please help
b = NEGATIVE TWO
scroll down to your first question for my solution
PLEASE POST ONCE
To solve the system of equations:
2a + b = 3 (Equation 1)
4a - 5b = 20 (Equation 2)
Your first step of multiplying the first equation by 5 to eliminate the b term was correct. It gives you:
10a + 5b = 15 (Equation 3)
Next, you need to add Equation 3 and Equation 2 together to eliminate the b term:
(10a + 5b) + (4a - 5b) = 15 + 20
Simplifying the equation:
10a + 5b + 4a - 5b = 35
(10a + 4a) + (5b - 5b) = 35
14a + 0 = 35
14a = 35
Now, divide both sides of the equation by 14 to solve for 'a':
14a/14 = 35/14
a = 2.5
So, the value of 'a' is 2.5.
To solve for 'b', substitute the value of 'a' back into one of the original equations. Let's use Equation 1:
2a + b = 3
Replacing 'a' with 2.5:
2(2.5) + b = 3
5 + b = 3
b = 3 - 5
b = -2
Therefore, the solution to the system of equations is a = 2.5 and b = -2.
If you checked your answers by substituting them back into the original equations and the equations didn't hold true, please double-check your calculations to make sure you haven't made any mistakes during the process.