Answer:
See explanation
Step-by-step explanation:
Given a system of equations, you can
- rewrite one of the equations and write the sum of two equations instead of the second equation;
- rewrite one of the equations and write the difference of two equations instead of the second equation;
- rewrite one of the equations and write the sum of the first equation multiplied by one nonzero number and the second equation multiplied by another nonzero number instead of the second equation.
These actions are called elementary row operations. Elementary operations with system of equations do not change the solution set.
Equation 1: x + y = 40 ; therefore y = 40 - x
Equation 2: 25x + 15y = 900
Find x first:
25x + 15 (40 - x) = 900
25x + 600 - 15x = 900
10x = 900 - 600
x = 300÷10
x = 30 hours Chris needs to spend for tutoring job
y = 40 - 30
y = 10 hours Chris needs to spend for referencing job
Step-by-step explanation:
g(x) = 3x - 2
g(-4) = 3(-4) - 2
= -12 -2
= -14
Answer:
The larger of the two is 44.67
Step-by-step explanation:
let the first number=x
let the second number=y
We can derive a system of equations using the mathematical statements
Their sum is 33:
x+y=33( call this equation 1)
Sum of first number and four times the second is -2:
x+4y=-2(call this equation 2)
Since the integer coefficients of x in both equations are the same we can quickly subtract one from the other to eliminate it
For this explanation, I choose to subtract equation 1 from 2
(x+4y=-2)-(x+y=33)=3y=-35
y=-35/3
Now plug in the value of y into any equation for that of x. Say we plug into equation 1
x+(-35/3)=33
x-35/3=33( multiply through by 3)
3x-35=99
3x=99+35
3x=134
x=134/3
Therefore,x=134/3 or 44.67 and y=-35/3 or -11.67
Answer:
3614 miles
Step-by-step explanation:
Given data
A plane flew for 2 hours at 467 mph
Let us find the distance covered
Speed= distance/time
Distance= speed*time
Distance= 467*2
Distance=934 miles
5 hours at 536
Let us find the distance covered
Speed= distance/time
Distance= speed*time
Distance= 536*5
Distance=2680 miles
Total distance
=2680+934
=3614 miles
