Solve the following simullateneous equation using a algebraic method (not graphically)

2x+5y=0

3x-4y=23

x = 5

y = - 2

Step-by-step explanation:

to solve this simultaneous equation using substitution method

solution

let

2x+5y=0 ... equation 1

3x-4y=23 ... equation 2

from equation 1

2x+5y=0 ... equation 1

2x = - 5y

divide both sides by the coefficient of x which is 2

we have,

2x/2 = - 5y/2

x = - 5y/2 ... equation 3

substitute for x = - 5y/2 in equation 2

3x-4y=23 ... equation 2

3 (-5y/2) - 4y = 23

-15y/2 - 4y = 23

multiply through by 2

-15y - 8y = 46

-23y = 46

divide both sides by the coefficient of y which is - 23

-23y/-23 = 46/-23

y = - 2

put the value of y = - 2 into equation 3

x = - 5y/2 ... equation 3

x = - 5 (-2) / 2

x = 10/2

x = 5

therefore the value of x = 5 and y = - 2 respectively