Answer:
w= 9
Step-by-step explanation:

Square both sides:
-4w +61= (w -4)²

Expand:
-4w +61= w² -2(w)(4) +4²
-4w +61= w² -8w +16
Simplify:
w² -8w +16 +4w -61= 0
w² -4w -45= 0
Factorize:
(w -9)(w +5)= 0
w -9= 0 or w +5= 0
w= 9 or w= -5 (reject)
Note:
-5 is rejected since we are only taking the positive value of the square root here. If the negative square root is taken into consideration, then w= -5 would give us -9 on both sides of the equation.
<u>Why </u><u>do </u><u>we </u><u>use </u><u>negative </u><u>square </u><u>root?</u>
When solving an equation such as x²= 4,
we have to consider than squaring any number removes the negative sign i.e., the result of a squared number is always positive.
In the case of x²= 4, x can be 2 or -2. Thus, whenever we introduce a square root, a '±' must be used.
However, back to our question, we did not introduce the square root so we should not consider the negative square root value.
Answer:
I like cheese
Step-by-step explanation:Milk and chees
Think of it like this:
of = multiplication of the equation
is= equals
and whatever you are looking for is your variable
so....
.40 times X = 56
Answer:
These lines will be perpendicular when m = ³⁄₂
Step-by-step explanation:
Two lines are perpendicular when the product of their gradients equal to -1. So:
m₁ * m₂ = -1
Let's get the first equation in gradient-intercept form (same as equation two).
2x + 3y = 4
3y = -2x + 4
y = -⅔x + ⁴⁄₃
We know the first gradient, and now we can find the gradient of the second line (which when multiplied will result in -1 as these lines are perpendicular). So:
-⅔ * m₂ = -1
m₂ = ³⁄₂
Answer:
Jack drove 65 miles per hour
It will take Jack 8 hours to drive 520 miles
Step-by-step explanation:
325 miles divided by 5 hours = 65 miles/hour
520 miles divided by 65 miles/hour = 8 hours