First bring all terms in 'a' to the left side of the formula by subtracting ac from both sides
ab - ac - cd = ac - ac
ab - ac - cd = 0
now add cd to both sides
ab - ac -cd + cd = cd
ab - ac = cd
now factor the left side by taking out the 'a'
a(b-c) = cd
now divide both sides by (b-c)
a = cd / (b-c)
done
Answer:
147°
Step-by-step explanation:
106°+139°+126°+141°+112°+129°+x =900°
753°+x = 900°
x = 900°-753°
x= 147° (sum of the interior angles of a heptagon=900°)
Answer:what is this
Step-by-step explanation: the answers are too small
