Answer:
The correct options are;
A. Let x equal the cost of a shirt and y equal the cost of a pair pants
B. Solve each equation for y
D. The solution is the point where the lines intersect
Explanation:
The cost of two shirts and five pants = $150
Three shirts and four pairs of pants = $190
Let x = The cost of a shirt and y = the cost of a pair of pants
We have;
2·x + 5·y = 150
3·x + 4·y = 190
We solve each equation for y, to get;
For the first equation, we have;
2·x + 5·y = 150
5·y = 150 - 2·x
y = 150/5 - 2/5·x = 30 - 2/5·x
y = 30 - 2/5·x
For the second equation, we have;
3·x + 4·y = 190
4·y = 190 - 3·x
y = 190/4 - 3/4·x = 47.5 - 3/4·x
y = 47.5 - 3/4·x
The solution is the point where the two lines intersect, which is given as follows;
y = y
47.5 - 3/4·x = 30 - 2/5·x
17.5 = 3/4·x - 2/5·x = 7/20·x
x = 20/7 × 17.5 = 50
The cost of a shirt = x = $50
The cost of a pair of pant = y = 30 - 2/5·x = 30 - 2/5 × 50 = 10
The cost of a pair of pant = $10.