Question

solve the following pairs of equation by cross multiplication method
X upon 3 + Y upon 5 equal to 1 and 7 x minus 15 y equal to 21​

Answer 1

Answer:Answer:X=3 and Y=0.

Step-by-step explanation:

X/3+Y/5=1. and 7x-15y=21.

X/3+Y/5=1

You first of all find the LCM of 3 and 5 which is 15.Then you will divide through by the 15 and cross multiple.So you will get something like....

5x+3y=15.

So now.

5x+3y=15.............equation 1

7x-15y=21............. equation 2

So am going to use the elimination method over here.

Multiple equation 1 by 10 and

Multiple equation 2 by 2.

10(5x+3y=15)=50x+30y=150.

2(7x-15y=21)=14x-30y=42.

Now add the two equations.Because we are eliminating Y.

=[50x+14x=192]

64x=192

X=192÷64

X=3.

Now put x=3 into equation 1

Which is the 5x+3y=15.

5(3)+3y=15

15+3y=15

3y=15-15

3y=0

y=0÷3

Y=0.

Therefore X=3 and Y=0.

Step-by-step explanation:

Answer 2

Answer:

hi

Step-by-step explanation:

thanks me later whatever