Q2 of 34 Page 170

Taking different numbers as x, y and compute x + y, x – y. Check whether the following hold for all kinds of numbers.

(x + y) – y = x

(x + y) – y = x

Let’s check for x = 3 and y = -3


L.H.S = (3 + (-3)) – (-3)


= (0) + 3


= 3


R.H.S = 3


= L.H.S


Hence, it works for x = 3 and y = -3


Let’s check for x = 4 and y = -4


L.H.S = (4 + (-4)) – (-4)


= (0) + 4


= 4


R.H.S = 4


= L.H.S


Hence, it works for x = 4 and y = -4


Similarly, we can check for other values too. It will follow.


More from this chapter

All 34 →
1

Take as x different positive numbers, negative numbers and zero, and compute x + 1, x – 1, 1 – x. Check whether the equations below hold for all numbers.

1 – x = – (x – 1)

 2

Taking different numbers as x, y and compute x + y, x – y. Check whether the following hold for all kinds of numbers.

(x + y) – x = y

 2

Taking different numbers as x, y and compute x + y, x – y. Check whether the following hold for all kinds of numbers.

(x – y) + y = x

 1

Check whether the equations are identities. Write the patterns got form each,on taking x = 1, 2, 3, 4, 5 and x = –1, –2, –3, –4, –5.

–x + (x + 1) = 1