SOLUTION: Solve the system of equations by the addition method. { 4x = 5y =5 { 16x - 20y =10 Select the correct answer is ether A,B OR C A) The sol

Algebra ->  Finance -> SOLUTION: Solve the system of equations by the addition method. { 4x = 5y =5 { 16x - 20y =10 Select the correct answer is ether A,B OR C A) The sol      Log On


   

Question 918656: Solve the system of equations by the addition method.
{ 4x = 5y =5
{ 16x - 20y =10













Select the correct answer is ether A,B OR C


A) The solution is_
B) There are infinitely many solutions
C) There is no solution
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
+4x+%2B+5y+=5....eq.1
+16x+-+20y+=10...eq.2....simplify, divide by 4
___________________
+4x+%2B+5y+=5....eq.1
+4x+-+5y+=10%2F4...eq.2............add both eq.1 and eq.2
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+4x+%2B+5y%2B4x+-+5y+=5%2Bcross%2810%295%2Fcross%284%292
+8x++=5%2B5%2F2
+8x++=10%2F2%2B5%2F2
+8x++=15%2F2
+x++=%2815%2F2%29%2F8
+x++=15%2F16

+4x+%2B+5y+=5....eq.1 substitute x
+cross%284%29%2815%2Fcross%2816%294%29+%2B+5y+=5
+%2815%2F4%29+%2B+5y+=5
+++5y+=5-%2815%2F4%29
+++5y+=20%2F4-15%2F4
+++5y+=5%2F4
+++y+=%28cross%285%291%2F4%29%2Fcross%285%291
+++y+=1%2F4


A) The solution is_( +15%2F16,+1%2F4) or as decimal ( +0.9,+0.25)

+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+1-4x%2F5%2C+4x%2F5+-1%2F2%29+