Question

find (x+y)÷(x_y)if x=5\2,y=_3/4
​

Answer 1

Answer:

What is the value of x and y if x+y=2 and x-y=5?

Your newborn may be vulnerable to these 6 serious diseases.

x, y={7/2, -3/2}

PREMISES

x+y=2 and x-y=5

(x+y)+(x-y)=2+5

(x+x)+(y-y)=2+5 (Addition and subtraction are commutative)

2x+0=7

2x=7

2x/2=7/2

x=

7/2 as an improper fraction or 3 1/2 as a mixed number (decimal: 3.5)

and,

if x=7/2, then

y=2-x (from the premises)

y=2–7/2

y=2–3 1/2

y=-[{3 1/2}–2]

y=

-3/2 as an improper fraction or -1 1/2 as a mixed number (decimal: -1.5)

PROOF

If x, y=7/2, -3/2, then the equations

(1) Y=(x+y=2)

Y=(7/2)+(-3/2)=2

Y=4/2=2 and

Y=

2

and,

(2) Y=(x-y=5)

Y=(7/2)-(-3/2)

Y=10/2

Y=

5