Answer:
-9 + 7√5.
Step-by-step explanation:
(3 - √5)(2 + 3√5)
= 3(2 + 3√5) - √5(2 + 3√5))
= 6 + 9√5 - 2√5 - 15
= -9 + 7√5.
Answer:
x = 24
Step-by-step explanation:
(2x - 4) + (3x + 5) + (2x + 11) = 180°
Combine like terms:
7x + 12 = 180
Subtract 12 on both sides:
7x = 168
Divide 7 on both sides:
x = 24
3x+2(4x-4)=3 - remove parentheses
3x+ 8x-8=3 - collect like terms
11x- 8 =3 - move the constant to the right
11x=3+8 - calculate
11x = 11 - divide both sides by 11
x= 1
a and c i think
the blue circle is all the people who had brothers one name was in the blue circle so one person had a brother but the in between part of the too circles are who had both a brother and a sister so the is one name in the between purple so you count that one to for brother and for sisters
there were 2 people that had brother
and four people that had sisters
and one that had both