how do I solve this

Question

Tony borrowed a total of $7000

 from two student loans. One loan charged 2%

 simple interest and the other charged 1.5%

 simple interest, both payable after graduation. If the interest he owed after 1

 year was $122.50

, determine the amount of principal for each loan

Answer 1

.02(X) + .015(7-X) = .1225

.02X - .015X = .1225 - .105

.005X = .0175

X = 0.0175/0.005 = 35 = $3,500 borrowed at 2%

$7,000- $3500 = $3,500 borrowed at 1.5%

$122.50/$7,000 = 1.75%

2 and 1.5% are equidistant from 1.75%

$3,500 borrowed at 2% and the other half

$3,500 borrowed at 1.5%

2% of 3,500 = 70

1.5% of 3,500 = 52.5

70+52.5 = 122.5