• # i need help on how to solve this problem

Posted by on June 20, 2021 at 3:28 pm

simultaneous equations someone please help me – Andre has more money than Bob. If Andre gave Bob $20, they would have the same amount. While if Bob gave Andre$22, Andre would then have twice as much as Bob. How much does each one actually have?

4 Members · 5 Replies
• 5 Replies
• ### Wuche Innocent

Member
July 14, 2022 at 12:51 pm

X+y=20….(1)

2x+y=22…(2)

Using elimination method, subtract eqn(1) from (2).

2x-x +y-y=22-20

X=2.

Solving for y in eqn(1); substitute the value of X=2

2+y=20

Y=20-2

Y=18

• ### D2

Member
December 20, 2022 at 8:57 am

hey that cant be right

because according to your definition they both have less than 20 dolllars

• ### D2

Member
December 20, 2022 at 9:02 am

a – 20 = b + 20… 1

2(b – 22) = a + 22… 2

We can juggle those around for

a = b +40 and

2b – 44 = a + 22 so 2b – 66 = a

The equations are now:

a = b + 40 and

a = 2b – 66

ELIMINATION METHOD:

b + 40 = 2b – 66 so 40 = b – 66 making b = 106.

Plug b = 106 into new equations 1 and 2 for:

a = 106 + 40 (new equation 1) and

a = 212 – 66 (new equation 2)

This gives a = 146 and b = 106

• ### D2

Member
December 20, 2022 at 9:04 am

For the purpose of the equations, I’ll call Andre and Bob a and b respectively.

a – 20 = b + 20 (equation 1)

2(b – 22) = a + 22 (equation 2)

We can juggle those around for

a = b +40 (equation 1r (re-arranged)) and

2b – 44 = a + 22 so 2b – 66 = a (equation 2r (rearranged))

The equations are now:

a = b + 40 (new equation 1) and

a = 2b – 66 (new equation 2)

Substitute from new equation 1 to new equation 2:

b + 40 = 2b – 66 so 40 = b – 66 making b = 106.

Plug b = 106 into new equations 1 and 2 for:

a = 106 + 40 (new equation 1) and

a = 212 – 66 (new equation 2)

This gives a = 146 and b = 106

• ### Nwamaka Okafor

Member
January 16, 2023 at 8:46 am

Please, how can I unlock the lessons here? Thanks

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