Find algebraically in RxR using substituting method the S. S. of the two equations:
X + y = 4
,
2 x - y = 5

Step-by-step explanation:

x + y = 4   equation 1

2x - y = 5  equation 2

using substitution method,

x= 4 - y  equation 3

substitute equation 3 into equation 2

2(4-y) -y = 5

8 - 2y - y = 5

8 - 3y = 5

-3y = 5 - 8

-3y = -3

divide through by -3

-3y/-3 = -3/-3

y = 1

substitue the value of y into equation 1

x + y = 4

x + 1 = 4

x = 4 - 1

x = 3

Hence, x = 3 and y = 1

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step-by-step explanation:

1+2+3+4+5+6+7+8+9+10 = 55

2*10 = 20

55-20 = 35