Every number times 5 the last digital number will be 5 or 0
Answer:
x = 19°
Step-by-step explanation:
we can see from observation that 22° and (3x+11)° are complementary. I.e they add up to 90°
hence
22 + (3x+11) = 90
22 + 3x+11 = 90
33 + 3x = 90 (divide both sides by 3)
11 + x = 30 (subtract 11 from both sides)
x = 30 - 11
x = 19°
The answer is b. There is a proof, but it is easily got by proving the other cases wrong.
Let the second side be x
then,
first side = twice the length of the second side
= 2x
third side = 20 feet less than three times the second side
3 (second side ) - 20
= 3 (2x) -20
= 6x - 20
perimete of a triangle = sum of all sides,
substitute the values we know,
and you'll be left with this equation
106 = x + 2x + 6x - 20
106+ 20 = 9x
126 = 9x
126/9 = x
14 = x
so,
measure of second side = x = 14 feet
measure of first side = 2x = 2 (14) = 28 feet
measure of thurd side = 6x - 20 = 6 (14)-20 = 84- 20 = 64 feet.