1) 8×( х +4 ) + 28=100 2) (25 -у) +54 =70

Question

1) 8×( х +4 ) + 28=100 2) (25 -у) +54 =70

Answer 1

8×(х+4)+28=100
100-28=72
72:8=9
х=9-4
х=5
------------------------------
8×(5+4)+28=100
100=100

(25-у)+54=70
70-54=16
у=25-16
у=9
------------------------
(25-9)+54=70
70=70

Answer 2

1) 8×(х+4)+28=100
 8х+32+28=100
8х+60=100
8х=100-60
8х=40
х=5
2) (25 -у)+54=70
 25-у+54=70
79-у=70
-у=70-79
-у=-9
у=9