Its same i think
100-40=60
130-70=60
For 5a+5b+5c=-20
A= -4 - b - c
B= -4 - a - c
C= -4 - a - b
———————————
4a+3b+3c=-6
A= -3/2 - 3b/4 - 3c/4
B= -2 - 4a/3 - c
C= -2 - 4a/3 - b
———————————
-4a+3b+3c=9
A= -9/4 + 3b/4 + 3c/4
B= 3 + 4a/3 - c
C= 3 + 4a/3 - b
Degrees (not like celsius or temperature though)
Desmos graphing calculator will draw this graph for you.
draw 2 curves
y = x^4 + x^3
and
y = 4x^2 + 4x
The roots are the points where the 2 curves intersect.
You can see by simple substitution that one root is zero.
x^4 + x^3 - 4x^2 - 4x = 0
f(2) = 16 + 8 - 4(4) - 4(2) = 0 so 2 is another root
f(-2) = 16 - 8 - 16 + 8 = 0 so -2 is another root
f(-1) = 1 - 1 - 4 + 4 = 0 so -1 is the other root
The answer is A
I guess you're supposed to simplify?



