Answer:
y = 460 miles per hr
x = 500 miles per hr
Step-by-step explanation:
Let the planes be X any
Let their speeds be xmiles/hr and ymiles/hr respectively
x = y + 40 (assuming X is faster by 40miles/hr)
Distance travelled by X to meet Y = 0.75x
Distance travelled by Y to meet X = 0.75y
0.75x + 0.75y = 720 --------1
Put x = y + 40 in eqn 1
0.75(y+40) + 0.75y = 720
0.75y + 30 + 0.75y= 720
1.5y = 690
y = 460 miles per hr
x = 460 +40
= 500 miles per hr
Answer:
- dimensions: 12 ft by 5 ft
- area: 60 ft²
Step-by-step explanation:
Let x represent the shorter dimension in feet. Then the longer one is x+7 and the Pythagorean theorem tells us the relation of these to the diagonal is ...
x² + (x+7)² = 13²
2x² +14x + 49 = 169 . . . . eliminate parentheses
x² +7x -60 = 0 . . . . . subtract 169 and divide by 2
(x +12)(x -5) = 0 . . . . factor the equation
x = -12 or +5 . . . . . . . only the positive value of x is useful here.
The short dimension is 5 ft, so the long dimension is 12 ft. The area is their product, 60 ft².
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<em>Comment on finding the area</em>
The quadratic equation above can be rearranged and factored as ...
x(x +7) = 60
Since the dimensions of the garden are x and (x+7), this product is the garden's area. This equation tells us the area is 60. We don't actually have to find the dimensions.
Answer:The one with -1. B
It was D on mine tho so check the graph
Step-by-step explanation:
I got it right on edg
Answer:
in this method a variable is expressed in terms of another variable from one equation and it is substituted in remaining equation.
Step-by-step explanation:
solve:x+2y=9 and 3x-y=13.
x+ 2y=9…be the first equation
3x-y=13…be the second equation
from first equation
x=9-2y…be the third equation substituting value of x from third equation in second equation, we get
3(9-2y)-y=13
or, 27-6y-y=13
or, y=2
now,
substituting value of y in third equation, we get,
x=9-2×2
=9-4
=5
the required value of x and y are 5&2
Answer: A (-2, 3)
Step-by-step explanation:
1. To know which oredered pairs does not lie on the graph, you must substitute the x-coordinate of each one of thm into the function and if you obtain the y-coordinate shown in that ordered pair, then that point lies on the graph.
2. Therefore, you have:
A. x=-2
(It does not lie on the graph).
B. x=--1
(It lies on the graph).
C. x=3
(It lies on the graph).
D. x=4
(It lies on the graph).
Therefore, the answer is the option A.