Peter R. answered • 04/23/23
Experienced Instructor in Prealgebra, Algebra I and II, SAT/ACT Math.
Nothing like problems that involve fractions and decimals at the same time!!
I suggest changing both to fractions, as 2/3 won't become a nice clean decimal when converted.
2x/3 - 2y/5 = 2 Mult by common denom of 15 to eliminate fractions.
10x - 6y = 30 divide by 2 to reduce to 5x - 3y = 15
0.15x + 0.006y = 0.93 Mult by 1000 to elim decimals
150x + 6y = 930 Divide by 6 to reduce to 25x + y = 155
So the new equations are:
25x + y = 155
5x - 3y = 15 Mult 1st equation by 3 and use elimination method.
75 x + 3y = 465
5x - 3y = 15
80x + 0 = 480 -> x = 6 Substitute in one of the original equations to find y.
0.15(6) + 0.006y = 0.93
0.006y = 0.93 - 0.90 = 0.03 -> y = 5 Solution at (6,5)
Suggest confirm by plotting with Desmos Graphing calculator.
