Kuta software - infinite pre-algebra
name
solving systems of equations by substitution
date
solve each system by substitution.
1) y = 7x-10
y=-3
2) y=-8
y=-2x - 12
3) y=6x
y=5x+7
4) y = 9x -9
y=9

Part 1) The solution of the system is the point (1,-3)

Part 2) The solution of the system is the point (-2,-8)

Part 3) The solution of the system is the point (7,42)

Part 4) The solution of the system is the point (2,9)

Step-by-step explanation:

Part 1) we have

----> equation A

----> equation B

Solve the system by substitution

Substitute equation B in equation A

Solve for x

Adds 10 both sides

Divide by 7 both sides

The solution of the system is the point (1,-3)

Part 2) we have

----> equation A

----> equation B

Solve the system by substitution

Substitute equation A in equation B

Solve for x

Adds 12 both sides

Divide by -2 both sides

The solution of the system is the point (-2,-8)

Part 3) we have

----> equation A

----> equation B

Solve the system by substitution

Substitute equation A in equation B

Solve for x

Subtract 5x both sides

Find the value of y

 ---->

The solution of the system is the point (7,42)

Part 4) we have

----> equation A

----> equation B

Solve the system by substitution

Substitute equation B in equation A

Solve for x

Adds 9 both sides

Divide by 9 both sides

The solution of the system is the point (2,9)

total amount to be paid = $19.5

step-by-step explanation:

given ,

original price = $25.99

discount = 25%

discount amount = 25% of original price

discount amount = 25/100   * 25.99

discount amount = $6.49

hence , the total amount to be paid = original price - discount amount

                                                            = $25.99 - $6.49

                                                            =$19.5

total amount to be paid = $19.5