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Which values for A and B will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

User Nbroeking
by
4.9k points

2 Answers

1 vote

Answer:

D

Explanation:

Edge2020

User Shikha Dhawan
by
5.0k points
6 votes

Answer:

a = -2 , b = -8

Explanation:

* Lets talk about the solution of the linear equations

- There are three types of the solutions of the system of linear equations

# If the two lines intersect each other, then there is one solution

- The equations are ax+ by = c , dx + ey = f

# If the two lines parallel to each other, then there is no solution

- The equations are ax+ by = c , ax + by = d in its simplest form ,

where a is the coefficient of x , b is the coefficient of y and

c , d are the numerical terms

# If the two lines coincide (over each other), then there are infinite

solutions

- The equations are ax+ by = c , ax + by = c in its simplest form, where

a is the coefficient of x , b is the coefficient of y and c is the

numerical term

* Lets solve the problem

∵ The system of equation is:

ax - y = 8 ⇒ (1)

2x + y = b ⇒ (2)

∵ The system create infinitely many solutions

∴ The lines are coincide

- The equations must be equal, then multiply equation(1) or (2) by -1 to

make the coefficient of y in the two equations equal

∴ -ax + y = -8

∴ 2x + y = b

∵ Their coefficients of x are equal

∵ Their coefficients of y are equal

∵ Their numerical terms are equal

∵ The coefficient of x in equation (1) is -a and in equation (2) is 2

∴ -a = 2 ⇒ multiply both sides by -1

∴ a = 2

∵ The numerical term in equation (1) is -8 and in equation (2) is b

∴ b = -8

* The values for a and b will create infinitely many solutions are -2 , -8

User Junier
by
5.4k points