Answer:
b = 
Step-by-step explanation:
b +
= 1
← change to an improper fraction
b +
= 
Multiply through by 12 ( the LCM of 3 and 4 ) to clear the fractions
12b + 8 = 15 ( subtract 8 from both sides )
12b = 7 ( divide both sides by 12 )
b = 
Answer:
55°
Step-by-step explanation:
d = 180 - 80 = 100
100 + 130 + 90 + (180 - 85) + (180 - c)
= 540
595 - c = 540
c = 595 - 540
c = 55°
Let's use a formula in order to find how much the interior angles are supposed to add up to.
(n-2)×180; n is the number of angles.
(5-2)×180= 3×180=540
We need for the interior angles to add up to 540. Let's make an equation.
100+102+108+121+x=540
431+x=540; let's find x.
540-431= 109
So, X= 109°
Answer:
a = -1
Step-by-step explanation:
The general equation for a straight line is y = mx+c, where m is the gradient/ slope, so m = -5. The first thing we need to do is find c, which we do by plugging in the x and y values that we already know: y = 7 and x = -2
7 = -5*(-2) + c
7 = 10 + c
c = 7-10 = -3
Now, we have the general equation of y = -5x -3 and we can use this to find a.
We'll treat a as x and y will be equal to 2:
2 = -5a -3
5 = -5a (Divide both sides by 5)
-a = 1 (now by -1)
a = -1
The descriminant is b^2-4ac so for 26 it would be -5^2 - 4 (1) (7). The quadratic formula is -B plus or minus the square root of b squared minus 4ac over 2a