Answer:
3x + x + 10 = 90
i am assuming that this is a right angle
90 = (3x) + (x+10)
1/2 or 0.5
Step-by-step explanation:
....
The regular price was $53.85
78% = $42
42 ÷ 78 x 100 = 100% = $53.85 (when rounded to 2 d.p)
5/ 1/3=1.6x2=3.2