Question

A shopper purchased 4 tables and 2 chairs for $200 and 2 tables and 7 chairs for $400. What is the cost of each table and each chair? And can you please explain the process using substitution please? Thanks.

Answer 1

4t+2c=200
2t+7c=400

I will solve for c in terms of t first
4t+2c=200
2c=200-4t
c=100-2t

Then I will substitute this in for c in the second equation to make it single variable
2t+7c=400
2t+7(100-2t)=400
2t+700-14t=400
300t=12
t=25 
Tables cost $25 each

Plug t back into one of the ORIGINAL equations to find the cost of chairs
4(25)+2c=200
100+2c=200
2c=100
c=50
Chairs cost $50 each

Hope this helps! :)