unit 2 lesson 20 - Noah and Lin are solving this system: 8x + 15 y = 58 12 x - 9y = 150 Noah multiplies the first equation by 12 and the second equation by 8, which gives: 96 x + 180 y = 696 96 x - 72 y = 1200 Lin says, “I know you can eliminate x by doing that and then subtracting the second equation from the first, but I can use smaller numbers. Instead of what you did, try multiplying the first equation by 6 and the second equation by 4." Do you agree with Lin that her approach also works? Explain your reasoning. What are the smallest whole-number factors by which you can multiply the equations in order to eliminate x ?

Noah and Lin are solving this system: 8x + 15 y = 58 12 x - 9y = 150 Noah multiplies the first equation by 12 and the second equation by 8, which gives: 96 x + 180 y = 696 96 x - 72 y = 1200 Lin says, “I know you can eliminate x by doing that and then subtracting the second equation from the first, but I can use smaller numbers. Instead of what you did, try multiplying the first equation by 6 and the second equation by 4." Do you agree with Lin that her approach also works? Explain your reasoning. What are the smallest whole-number factors by which you can multiply the equations in order to eliminate x ?

20 viewed last edited 3 months ago

unit 2 lesson 20 CCSS.HSA.CED.A.1.Q.A1.SIV.20 CCSS.HSA.CED.A.3.Q.A1.SIV.20 CCSS.HSA-REI.B.3.Q.A1.SIV.20 HSA-CED.A.1 HSA-CED.A.3 HSA-REI.B.3 writing and solving inequalities in one variable solving system of equations elimination method

Jordan Perez-Salvador (Student, 9^th Grade)

Sangeetha Pulapaka (last edited 3 months ago) (Expert, Educator @Qalaxia)

Multiplying the first equation with 6 gives us

48 x + 90 y = 348

Multiplying the second equation with 4 gives us

48 x - 36 y = 600

Now we can solve these by elimination method,

So Lin's approach also works.

2.We can multiply the first equation by 3 and the second equation by 2.