Firstly, It says that the two triangles are similar .
The scale factor is 2 as 12 / 6 = 2
25 + 85 = 110
180 - 110 = 70.
70 degrees
A quadratic equation is set up in the form of ax² + bx +c
First set equation = to 0
0= x² - 5x - 24
Next plug into quadratic formula( -b Plus or minus the √b²-4ac) ÷ 2a
[10 plus or minus √(25² - 4×1×24)] ÷ 2
Solve for inner parenthesis first
√625- 96 = √529
Now set up two equations
(10 + √529) ÷2 = x = 16.5
(10 - √529) ÷2 = x = -6.5
So therefore x = 16.5 and -6.5
In 10/8 divided by 1/6, you have to do the reciprocal of 1/6 and the dividing symbol... so now it should look like 10/8 times 6/1 . Then you just multiply! <span />