add 3.7 and 4.45 make sure to change it back to standard you'll get 815000000000000000000. move decimal between first and second digit which means you moved it to the left 18 times and your answer will be 8.15 x 10 ^18 I hope its right :( please don't judge if wrong :((( lol
Answer:
x = -1 and x = 5
Step-by-step explanation:
<em>What are the solutions of the equation (x – 3)² + 2(x – 3) -8 = 0? Use u substitution to solve.</em>
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(x – 3)² + 2(x – 3) -8 = 0 -------------------------------------------------------(1)
To solve this problem, we will follow the steps below;
let u = x-3
we will replace x-3 by u in the given equation:
(x – 3)² + 2(x – 3) -8 = 0
u² + 2u -8 = 0 ----------------------------------------------------------- --------------(2)
We will now solve the above quadratic equation
find two numbers such that its product gives -8 and its sum gives 2
The two numbers are 4 and -2
That is; 4×-2 = -8 and 4+(-2) = 2
we will replace 2u by (4u -2u) in equation (2)
u² + 2u -8 = 0
u² + 4u - 2u -8 = 0
u(u+4) -2(u+4) = 0
(u+4)(u-2) = 0
Either u + 4 = 0
u = -4
or
u-2 = 0
u = 2
Either u = -4 or u = 2
But u = x-3
x = u +3
when u = -4
x = u + 3
x = -4 + 3
x=-1
when u = 2
x = u + 3
x = 2 + 3
x=5
Therefore, x = -1 and x =5
x
9514 1404 393
Answer:
c. x = 7-t; y = -1/(t -7)
Step-by-step explanation:
To find the parametric equation for x, use the equation for t and solve for x.
t = 7-x
x = 7 -t . . . . . . add x-t to both sides
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To find the parametric equation for y, substitute the equation for x.
y = 1/x
y = 1/(7-t)
To make this match the available choices, we need to multiply numerator and denominator by -1.
y = -1/(t -7)
The parametric equations are ...
x = 7 -t; y = -1/(t -7) . . . . . . matches choice C
