Answer:
x = 21.
Step-by-step explanation:
AS there are parallel lines:
4/12 = 7/x
4x = 84
x = 84/4 = 21.
Answer:
Multiply 1014 by 6.444 and you should get
Step-by-step explanation:
6534. 216 x
Answer:
2. x
² + y
²
= 4
3. x² + y² = 23
Step-by-step explanation:
The equation of a circle with center
(
a
,
b
) and radius r is:
(
x
−
a
)²
+ (
y
−
b
)
² = r
²
Explanation:
Here,
a
=
0
, b
=
0
, r
=
2
The equation is:
(
x
-0
)
² + (
y
-0
)
² = (
2 )
²
that is: x
² + y
² = 4
Thus:
x
² + y
²
= 4
3. Each point on a circle has the same distance from the center. This distance is the radius r of the circle.
Here,
(
-3
,
4
) is a point on the circle, meaning that the radius of the circle is the distance between (
0
,
0
)
, the center, and (
-3
,
4
)
.
thus a circle centered on the origin will have an equation of:
x² + y² =r²
And, (
-3
,
4
) lies on the circle, we have:
(-3)² + (4)² = r²
9 + 14 = 23
substituting;
x² + y² = 23
Answer:
Step-by-step explanation
- Let x be the number of adults and y the number of kids
We can then write this two equations :
x+y= 33
15x+7y= 311
- let's solve the two eaquations
to do that we should combine them both in a way that help us get rid of one of the variables.
Let's multiply the first equation by -7 to get rid of y by adding it to thr second equation
-7x-7y= -231
now add both equations .
15x+7y-7x-7y=311-231
we get : 8x = 80
as you notice y is gone and we get a classic easy equation to solve
x= 80/8
= 10
so the number of adults is 10
let's go back to the first equation ( x+y= 33) and replace x with 10
10+y= 33
y= 33-10
=23
let's check using the second equation :
(10*15)+(23*7) = 311
that is true
so :
- the number of adults is 10
- the number of kids is 23
Step-by-step explanation:
The expression for “the difference of 10 and x.”
can be given in two ways:
10 - x
or
x - 10
