Answer:
x = 1/5
y = 6
Step-by-step explanation:
System:
{5x + y = 7
{20x + 2 = y
First equation:
5x + y = 7 -> y = -5x + 7
Plug into second equation:
20x + 2 = -5x + 7
Subtract 2 from both sides:
20x = -5x + 5
Add 5x to both sides:
25x = 5
Divde both sides by 25:
x = 5/25 -> 1/5
~~~~~~~~~~~~~~~~~~~~~~~~~~~`
Come back to the first equation:
5x + y = 7
Plus in our x:
5(1/5) + y = 7
Multiply:
1 + y = 7
Subtract 1 from both sides:
y = 6
Hope this helps, have a nice day! :D
In the first figure we have an angle that subtends a diameter. Those are always right angles, so
Answer: x=90 degrees
In the second figure we have to notice that the measure of arcs and central angles are interchangeable -- the measure of an arc is its central angle.
The units are implicitly degrees; the 10 should say 10°
These are supplementary angles so they add to 180°
3x + (7x + 10) = 180
10x = 170
x = 17
Answer: x=17
17° would be more accurate but the units are a bit ambiguous here so I'll leave it.
Answer:
x=4 and y=1
Step-by-step explanation:
4x-y=15
2x+y=9
6x=24
x=24/6
x=4
4x-y=15
4(4)-y=15
16-y=15
-y=15-16
-y=-1 Divide both sides by -1
y=1
Answer:
Step-by-step explanation:
b)
