An investor buys $15,000 worth of stocks. The price of one kind of stock is $35 per share, and the price of the other kind of stock is $45 per share. If 100 shares of the more expensive stock was bought, find the number of shares of the cheaper stock bought.

The value of x in this system of equations is 1. 3x + y = 9 y = –4x + 10 substitute the value of y in the first equation: combine like terms: apply the subtraction property of equality: apply the division property of equality: 3x + (–4x + 10) = 9 –x + 10 = 9 –x = –1 x = 1 what is the value of y?