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vazorg [7]
3 years ago
5

Whats the solutions to

Mathematics
2 answers:
Volgvan3 years ago
6 0
X+2y=4
Multiply both side by 2
x*2+2y*2=4*2
2x+4y=8

2x-2y=5
Next, use substitute property
2x+4y=8
-
2x-2y=5
=
6y=3
Divided both side by 6
6y/6=3/6
y=0.5

x+2y=4
Substitute y with 0.5
x+2(0.5)=4
x+1=4
Subtract 1 to each side
x+1-1=4-1
x=3, so the solution to this equation is (3,0.5)

7x-2y=-20
Multiply both side by 2
7x*2-2y*2=-20*2
14x-4y=-40

9x+4y=-6
Then, Use substitute property
14x-4y=-40
+
9x+4y=-6
=
23x=-46
Divided 23 to each side
23x/23=-46/23
x=-2

7x-2y=-20
Substitute x with -2
7(-2)-2y=-20
-14-2y=-20
Add 14 to each side
-14-2y+14=-20+14
-2y=-6
Divided -2 to each side
-2y/-2=-6/-2
y=3, so the solution to this equations are (-2,3)

2x+y=7
-3x+y=2
Then, use substitute property
2x+y=7
-
-3x+y=2
=
5x=5
Divided 5 to each side
5x/5=5/5
x=1

2x+y=7
Substitute x with 1
2(1)+y=7
2+y=7
Subtract 2 to each side
2+y-2=7-2
y=5, so the order pair is (1,5). Hope it help!
andrezito [222]3 years ago
4 0
1st problem:
Solve for x, then substitute that in for x in the second equation. Solve for y. Substitute value of y into first equation. Solve for x. This gives the point of intersection.
\left \{ {{x+2y=4} \atop {2x-2y=5}} \right.  \\  \\ x=4-2y \\ 2(4-2y)-2y=5 \\ 8-8y-2y=5 \\ -10y=-3 \\ y=\frac{3}{10}  \\ x=4-2(\frac{3}{10} )= \frac{23}{5}  \\ 
(  \frac{23}{5}, \frac{3}{10} )

2nd problem:
Multiply the first equation by 2 and then add the two equations. Solve for x. Substitute the value for x into the second equation. Solve for y. This gives the point of intersection.
\left \{ {{7x-2y=-20} \atop {9x+4y=-6}} \right. \\ \\ 14x-4y=-40 \\ 23x=-46 \\ x=-2 \\ 7(-2)-2y=-20 \\ -2y=-34 \\ y=17 \\ (-2,17)

3rd problem:
Solve for y in the first equation and substitute that into the second equation. Solve for x. Substitute into first equation. This gives the point of intersection.
\left \{ {{2x+y=7} \atop {-3xy=2}} \right. \\ \\ y=7-2x \\ -3x+(7-2x)=2 \\ -5x=-5 \\ x=1 \\ y=7-2(1)=5
\\ (1,5)


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Alborosie
Angle B is HALF of the sum of the two angles it intercepts.

Since it intercepts 48 and 142 degrees, simply add them add divide by 2:
B = (48 + 142)/2
B = 190/2
B = 95

The measure of angle B is 95 degrees.
-T.B.
4 0
3 years ago
A lake has a large population of fish. On average, there are 2,400 fish in the lake, but this number can vary by as much as 155.
AleksAgata [21]

Answer:

Minimum population of fish in lake = 2400 - 155 = 2245

Maximum population of fish in lake = 2400 + 155 = 2555

Step-by-step explanation:

population of fish in lake = 2400

Variation of fish = 155

it means that while current population of fish is 2400, the number can increase or decrease by maximum upto 155.

For example

for increase

population of fish can 2400 + 2, 2400 + 70, 2400 + 130 etc

but it cannot be beyond 2400 + 155.

It cannot be 2400 + 156

similarly for decrease

population of fish can 2400 - 3, 2400 - 95, 2400 - 144 etc

but it cannot be less that 2400 - 155.

It cannot be 2400 - 156

Hence population can fish in lake can be between 2400 - 155 and 2400 + 155

minimum population of fish in lake = 2400 - 155 = 2245

maximum population of fish in lake = 2400 + 155 = 2555

4 0
3 years ago
received a monthly salary of 2500 together with a commission of 5% on answers over 5000 per month calculate his gross salary in
sergejj [24]

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2 years ago
On a piece of paper, use a protractor to construct right triangle DEF with DE=4 in. , m∠D=90° , and m∠E=45° .
uysha [10]

Answer: DF = 4 in

Step-by-step explanation:

Here in triangle DEF,

In which DE = 4, m\angle D=90^{\circ} , and m\angle E=45^\circ}

Since, tan E = \frac{FD}{DE}

⇒ tan 45^{\circ} = \frac{FD}{DE}

⇒  1 = \frac{FD}{4}

⇒  FD = 4

Thus, first option is correct.

8 0
3 years ago
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kirill [66]

Answer:

$6.80

Step-by-step explanation:

Divide $34 by 5

and you get $6.80

7 0
3 years ago
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