Question

detreminati nr a si bpt care a*b+5a+3*b=15

Answer 1

a*(b+5)+3b=15
a*(b+5)=15-3b
a=15-3b/b+5
deci [15-3b/b+5](b+5)+3b=15   15-3b+3b=15(b+5)  15=15b+75  15b=-60  b=-60/15=-4  b=-4

a=15-3*-4/-4+5
a=15+12/1  a=27/1=27  a=27
proba 27*-4+5*27+3*-4=-108+135-12=27-12=15