Answer:
8
Step-by-step explanation:
a A + b A where A is a matrix and a and b are scalars
( a+b) A
3+5
= 8![\left[\begin{array}{cc}-1&2\\4&-5\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-1%262%5C%5C4%26-5%5Cend%7Barray%7D%5Cright%5D)
<span><span>A cargo plane flew to Moscow and back.
It took six hours longer to go there than it did to come back.
The average speed on the trip there was 152 mph.
The </span></span><span>average speed on the way back was 380 mph.
How many hours did the trip there take?
(x + 6)152 = 380x
228x = 912
x = 4
The trip there took 10 hours.</span>
Explanation:
The perimeter of the track is the two circumferences of the semicircles (when combined, they form one circle, so we can just find the circumference of the circle) added to the lengths of the rectangle (
160
meters).
To find the circumference of the circle, we need to know the diameter.
Circumference of a circle:
d
π
or
2
r
π
, where
d
represents diameter and
r
represents radius
The diameter of the circle happens to be the same as the width of the rectangle. We know that the area of a rectangle is found by multiplying its length by its width. We know that the area is
14400
and that its length is
160
.
Width: area divided by length
14400
160
=
90
The diameter of the circle and the width of the rectangle is
90
meters.
Circumference:
90
⋅
π
=
90
π
→
If you are using an approximation such as 3.14 for
π
, multiply that by 90
Add
160
⋅
2
to the circumference since the lengths of the rectangle are also part of the perimeter.
160
⋅
2
=
320
90
π
+
320
i hope it helps you ok please mark ❣️ me as brainlist
Answer:The measure of angle RST is 120\°
Step-by-step explanation:
see the attached figure to better understand the problem
we know that
m<RST=(6x+12)\° -----> equation A
m<RST=78\°+(3x-12)\° -----> equation B
equate equation A and equation B
(6x+12)\°=78\°+(3x-12)\°
8 and 5 multiply to 40 but subtract to 3.