If you move the decimal point left until it is just to the right of the most-significant digit, the number of places you moved it is the power of ten that your new number is multiplied by.
Then multiplication can proceed in the usual way, taking into account the rules of exponents.
D=60. multiply both sides of the equation by 4 since it’s a factor, giving you 2d-20-d=40. since there are like terms with d, collect them to get d-20=40 and move 20 to the right and change it’s sign. that will give you d=40+20, then calculate to get d=60. hope this helped! :)
Answer:
Cosine
Step-by-step explanation:
Cosine = 
Cos 70 = 
0.633 =
0.633 x 8 = x 8
5.064 = x
This one is so easy that your brain refuses to accept it.
It's looking for a harder answer, but can't find it !
You're totally correct, as far you went. x² + 2x does = -1
Now add ' 1 ' to each side: x² + 2x + 1 = 0
Can you factor that quadratic ?
Can you mash it through the quadratic formula ?
Actually, it's the simplest possible perfect square.
x² + 2x + 1 = (x + 1)²
So the solutions of x² + 2x + 1 = 0 are both x = -1 .
Don't say anything.
I know it's embarrassing.
