4. Angel had money saved for Christmas shopping. He spends $12.15 on the first gift he buys. He has $40.59 left in his account. Write and solve an equation to determine how much money Andrew had before he bought the gift. ​

$12.15+$40.59= 52.74

Abit confused about what you mean, but i think you might be referring to slope intercept form: y = mx + bin that case b, or the y intercept is already given.(0,-1)find the slope by using the formulay2 - y1/x2 - x1the final slope will be 4/2, equivalent to 2.now your equation should look like thisy = 4/2x -1sorry if this didn’t you out!