Answer:
x=3
Step-by-step explanation:
-8x-(8x)=-48
-8x-8x=-48
Collect like terms
-16x=-48
Divide both sides by-16
x=3
y = x² - 4x + 8
4x + y = 12
4x + y = 12
4x + (x² - 4x + 8) = 12
x² + 4x - 4x + 8 = 12
x² + 8 = 12
- 8 - 8
x² = 4
x = ±2
4x + y = 12
4(2) + y = 12
8 + y = 12
- 8 - 8
y = 4
4x + y = 12
4(-2) + y = 12
-8 + y = 12
+ 8 + 8
y = 20
(x, y) = (2, 4) and (-2, 20)
Answer:
40 km on the highway
30 km on the city roads
Step-by-step explanation:
Let x = highway
Let y = city road
The time formula: time = distance / speed.
1) Since we do not know the distance travelled on the highway and city roads but we do know the total time taken, we can say x + y = 70. Set the distances x and y and all equated to 2 hours, since we do not know them, nor do we know the time. This is called a system of equations.
x + y = 70
x/80 + y/20 = 2
2) Solve the system of equations using substitution.
x = 70 - y
---------------
70 - y/80 + y/20 = 2
70 + 3y/80 = 2
y = 30
---------------------------------
x + 30 = 70
x = 70 - 30
x = 40
Therefore, the delivery truck travelled 40 km on the highway and 30 km on the city roads.
A=14 <span>the number of pounds of apples Angelica bought.</span>
Please use " ^ " to indicate exponentiaton: <span>Use the equation
350 = (270)(1.05)^x.
Take the log of both sides:
log 350 = log 270 + x*log 1.05.
Subtr. log 270 from both sides:
log 350 - log 270 = x*log 1.05
log 350 - log 270
Sove for x: x = -------------------------
log 1.05
2.544- 2.431
Evaluate this using a calculator. x = ------------------
0.0212
x is then approx. 5.33, or 5 1/3 years.
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