Answer:
Choice A
Step-by-step explanation:
In each case, each equation has an equation of a line in y = mx + b form equaling another equation of a line in y = mx + b form. If the two sides are equal, it is the same equation, there are infinitely many solutions. If the sides are different, then if the slopes are different, the lines intersect at one point, and there is exactly 1 solution. If the slopes are equal, the lines are parallel, and there is no solution.
(Choice A) -10x-10=-10x-10
In Choice A, both sides of the equation are equal, so there are infinitely many solutions.
(Choice B) 10x-10=-10x+10
(Choice C) 10x-10=-10x-10
(Choice D) -10x-10=-10x+10
In choices B through D, the two sides are not equal, so there is either 1 solution (B and C since they have different slopes) or no solution (D since the slopes are equal).
It takes about 4 days for the temperature to decrease by 9°F.
An equation is an expression that shows the relationship between two or more variables or numbers.
Let x represent the number of days. Given that the temperature drop decreased by 1 1/2°F each day (- 1 1/2), for it to decrease by 9°F (-9):
-1 1/2 * x = -9
-1.5x = - 9
x = 4 days
It takes about 4 days for the temperature to decrease by 9°F.
Answer:
Bc = √63 ft
Step-by-step explanation:
Here, we want to get the length of BC
As we can see, there is a right angled triangle ABC, with 12ft being the hypotenuse and 9 ft the other side
So we want to get the third leg which is BC
we can use the Pythagoras’ theorem here
And that states that the square of the hypotenuse equals the sum of the squares of the two other sides
let the missing length be x
12^2 = x^2 + 9^2
144 = x^2 + 81
x^2 = 144-81
x^2 = 63
x = √63 ft
