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Which statement describes the system of equations?

-5x-4y=-4
25x+ 20y = 20
It has one solution (4,-4).
It has one solution (8,-9).
The system has no solution.
The system has infinitely solutions.

User Jtht
by
4.7k points

2 Answers

1 vote

Answer:

The system has infinitely solutions.

Explanation:

User Bigmax
by
5.5k points
1 vote

Answer: The system has infinitely solutions.

Explanation:

The given system of equations : -


-5x-4y=-4\\\Rightarrow\ -5x-4y+4=0-----(1)\\\\25x+ 20y = 20\\\Rightarrow\ 25x+20y-20=0----(2)

Compare these equation with
a_1x+b_1y+c_1=0 and
a_2x+b_2y+c_2=0 respectively , we get


a_1=-5\ ;b_1=-4\ ;\ c_1=4


a_2=25\ ;b_2=20\ ;\ c_2=-20

Now,
(a_1)/(a_2)=(-5)/(25)=(-1)/(5)


(b_1)/(b_2)=(-4)/(20)=(-1)/(5)


(c_1)/(c_2)=(4)/(-20)=(-1)/(5)

Thus ,
(a_1)/(a_2)=(b_1)/(b_2)=(c_1)/(c_2)=(-1)/(5)

It means these lines are coincident, thus they have infinite number of solutions.

User Keith Harrison
by
5.2k points