<span>5x - y = 15 (1)
-10x+2y=-30 (2)
multiply (1) by 2
10x - 2y = 30
</span>-10x + 2y = -30 (2)
<span>---------------------------add
0 = 0
answer
</span><span>infinitely many solutions</span><span>
</span>
Step-by-step explanation:

( vertically opposite angles)



Answer:

Step-by-step explanation:
Flipping a coin and rolling a number cube are both independent events. Independent events do not rely on the outcome of any previous events. This means that whatever you flip on the coin will have no effect on whatever you roll on the number cube and each flip of the coin or roll of the cube has the same probability as the flip or roll before.
The probability of getting tails on a coin toss is: 
The probability of getting a number less than 3 (so 1 or 2) on a number cube is: 
Since we are combining these events, we need to multiply the fractions together to get our overall probability:
*
=
4x = 76
Where x is how many awnsers he got correct and 4 how many points each correct question awnsered.
Now you just have to isolate x by dividing both sides of the equation by 4
4x/4 = 76/4
x = 19
So he got 19 questions right and 10 awnsers wrong. In total there were 29 questions on his test