I would multiply to get rid of the decimals and work with whole numbers.
Since we have numbers that are "hundredths", we would need to multiply every number by 100.
60d + 5e = -450
-12d + 30e = 276 Now that the decimals are gone, if we multiply the second equation by 5 the "d's" will cancel.
60d + 5e = -450
-60d + 150e = 1380
155e = 930
e = 6
Now plug 6 back in for e and solve for d.
60d + 5(6) = -450
60d + 30 = -450
60d = -480
d = -8
(-8, 6)
If you'd rather work it with decimals just let me know.