Answer:
Step-by-step explanation:
Cross multiplication can be used but not in the beginning. First x should be isolated.

Now subtract
from both sides

In this stage, cross multiplication can be used.

Answer:
<h2>x = 12</h2>
Step-by-step explanation:
ΔADC and ΔCDB are similar (AA). Therefore the sides are in proportion:

We have AD = 16, DC = x, DB = 9. Substitute:
<em>cross multiply</em>

Answer:
Take 7.1-4.9=x
Step-by-step explanation:
Answer:
19.25
Step-by-step explanation:
77*(1/2)²= 77/4 = 19.25