Question

jim and carina have jobs buying and selling pet lizards. Jim sold 10 geckos and 8 iguanas for a profit of $122.00. Carina sold 9 geckos and bought 8 iguanas for a profit of $11.00. Find the price of one gecko and an iguana, using the addition method for solving systems.

Answer 1

The price of one gecko is $7.00 and the price of one iguana is $6.50

Explanation:

Let

x ----> the price of one gecko

y ----> the price of one iguana

we know that

Jim

`10x+8y=122.00` ----> equation A

Carina

`9x-8y=11.00` ----> equation B

Note: the coefficient of y is negative because Carina bought 8 iguanas

Solve the system by addition

Adds equation A and equation B

`10x+8y=122.00\\9x-8y=11.00\\----------\\10x+9x=122.00+11.00\\19x=133.00\\x=7.00`

Find the value of y

substitute the value of x in any equation

`10(7.00)+8y=122.00`

`70.00+8y=122.00`

`8y=122.00-70.00`

`8y=52.00`

`y=6.50`

therefore

The price of one gecko is $7.00 and the price of one iguana is $6.50