Question

help me to solve them all questions
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Answer 1

Answer:

Step-by-step explanation:ans 5

multiply both eq with 10 we get

2x +3y =13 .......i

4x + 5y = 23  ......ii

from i eq  we get 3 y = 13-2x

             y = 13-2x  divide by 3

 subsituting the value of y in eq 2  we get

4 x + 5(13 -2x) / 3 = 23

 4 x + 65-10x /3 =23

12 x +65 - 10x /3 = 23

2x+65/3 =23

2x +65 =69

x =2

put value of x in eq i we get

2*2 +3y =13

3y = 9

y = 3

         

ans 2 let us assume 6+√2 is a rational. and can be expressed in the form of a/b , where a and b are coprime positive integers and b is not = 0

6+ √2 = a/b

a/ b -2 =√3 ....i

a-2b  divide by b = √3

A-2b /b = ratinal no.

thus from i eq √3 is a rational no.

but it contradicts the fact that √3 is an irrational no. so 6+√3 is an irrational no.