Answer:
2 solutions
Step-by-step explanation:
x^4-6x^2-7=0
Replace x^2 by y
(x^2)^2-6x^2-7=0
y^2-6y-7=0
D=b^2-4ac= (-6)^2-4*1*(-7)= 36+28=64
sqrtD=8
y1=(-b-sqrtD)/2a=-2/2=-1
y2= (-b+sqrtD)/2a=14/2=7
x^2=-1(n0 roots) x^2=7 x=sqrt7 or x=-sqrt7
2 roots
Answer:
C. Elise should multiply both sides by 8.
Step-by-step explanation:
We need to undo what is being done to x
We are dividing x by 8, so to undo it we do the opposite.
The opposite of dividing is multiplication.
We multiply each side of the equation by 8
Divide 768 hours by 12 hours and u will get a answerr
Answer:
y = -2x-5
Step-by-step explanation:
So to calculate the slope the equation is y1-y2/x1-x2. We substitute in two points, let's use (-3,1) as x1 and y1, and (1,-7) as x2 and y2. Put those points in the equation and you get -7-1/1-(-3), which is -2. Now you have y=-2x+b
To get b plug in a pair of points to the equations, say (1,-7). -7=-2(1)+b, solve that and you get b=-5.
So y=-2x-5.