Answer:
Step-by-step explanation:
3/4=75%
75%x64=48 math books
math books divided by total # of books = percent of math books
(Substitute that^) 48 divided by 64 = 0.75 = 75%.
A quicker way to solve this if you don't need to show work is to see that 3/4 = 75% and since 3/4 of the books are math, you can substitute 3/4 for 75% and now you know 75% of the books are math books. Hope this helps!
Y=2x
so what you do is sub 2x for y in the top equation
x^2+(2x)^2=5
x^2+4x^2=5
5x^2=5
divide both sides by 5
x^2=1
sqrt both sides
x=1 or -1
sub back
y=2x
y=2(-1)
y=-2
y=2(1)
y=2
the solutions are (1,2) and (-1,-2)
Question 1:
the two sides are both 21 making this an isoceles triangle. In an isoceles triangle not only are two sides the same, but the bottom two angles are as well.
We know a triangle has 180°. We know the top Angle is 38° and the bottom two are the same.
we can setup an equation like this
2x + 38 = 180.
Subtract 38: 2x = 142
Divide by 2: x = 71
question 2:
the hash marks on the two sides mean they are the same length. So we are dealing with an isoceles triangle again.
Since the bottom two angles are the same, we know Angle B is also 47°.
Knowing that 180° are in a triangle, and the two 47° angles make up 94°, we know the top Angle is 86°.
The two curve lines at the top represent that those angles are the same. since we know that whole top Angle is 86, we divide that by two.
86 / 2 = 43. so y = 43°
to find x, we once again know 180° in a triangle. so take the 47° from the corner and the 43° from the top to find x.
47 + 43 + x = 180
Subtract 47 & 43: x = 90
$4.30
Do ten times $3.57 and subtract it from $40
Answer:
x= 3/5 or x= 0.6
Step-by-step explanation: