Answer:
x = 0
y = 5
z = -5.
Step-by-step explanation:
X-5y-z=-20
-2x-y-6z=25
-x-4y-z=-15
Add equation 1 and 3:
-9y - 2z = -35 .......... A
Multiply the first equation by 2:
2x - 10y - 2z = -40
Now add this to equation 2:
-11y -8z = -15.............B
Now multiply equation A by -4:
36y + 8x = 140.........C
Add equations B and C:
25y = 125
y = 5.
Substitute for y in equation A:
-9*5 - 2z = -35
2z = -45 + 35 = - 10
z = -5.
Now find x by substituting for y and z in the first equation:
x - 5(5) - (-5) = -20
x - 20 = -20
x = 0.
The appropriate expression to identify the amount of formalin is: x = 3200 ÷ 100 × 44%
<h3>How to identify the amount of formalin?</h3>
To calculate the amount of formalin in this substance we must perform the following mathematical operation:
- 3200 ÷ 100 = 32
- 32 × 44% = 1,408
According to the above, the mathematical expression would be:
Learn more about mathematical expression in: brainly.com/question/14462529
#SPJ1
Grab some paper, a pencil, and a ruler. Make a 6 by 6 square
Answer:
the cyclists rode at 35 mph
Step-by-step explanation:
Assuming that the cyclists stopped, and accelerated instantaneously at the same speed than before but in opposite direction , then
distance= speed*time
since the cyclists and the train reaches the end of the tunnel at the same time and denoting L as the length of the tunnel :
time = distance covered by cyclists / speed of cyclists = distance covered by train / speed of the train
thus denoting v as the speed of the cyclists :
7/8*L / v = L / 40 mph
v = 7/8 * 40 mph = 35 mph
v= 35 mph
thus the cyclists rode at 35 mph
Irrational as 0.75 x 0.75 x 3.14......
