If x and y are two real numbers such that 3x + 2y = 5 and 5x + 4y = 9, then 4x + 3y =?
A. 1
B. 2
C. 5
D. 6
E. 7
Correct Answer: E
Explanation
To find the value of given the equations:
1.
2.
we can solve this system of linear equations. Here’s the step-by-step method:
Step 1: Solve the System of Equations
Equation 1:
Equation 2:
To eliminate one of the variables, we can multiply Equation 1 by 2 to align the coefficients of :
Now subtract Equation 2 from this result:
Step 2: Substitute into Equation 1 to find :
Substitute into Equation 1:
Step 3: Calculate using and :
The value of is 7
The correct answer is E. 7