While it's pretty obvious to most of us that
-13x=90-2y
-6x=48-2y
is a system of linear equations, it'd be well to include that info plus the instructions "solve this system of linear equations."
Subtract the 2nd equation from the first:
-13x=90-2y
+6x=-48+2y
-----------------------
-7x = 42. Then x = -42/7, or x = 6.
Now subst. 6 for x in either one of the given equations. Suppose we use the 2nd equation:
-6x=48-2y
Then -6(6)=48-2y, or -36 = 48 - 2y, or 2y = 48+ 36 = 84. Then y = 42.
The solution is (6, 42).
Answer:
Answer is A. 36x-11y
Step-by-step explanation:
34x-12x+14x-18y+7y
=22x+14x-18y+7y
=36x-11y
Answer:
40 classrooms
Step-by-step explanation:
Divide 1200 by 30.
1200÷30=40
If 390 students are boys just subtract 390 from 1200.
1200-390= 810
There must be 810 girls if there are 390 boys
Answer:
Probability of choosing a penny at random is 1/5 or 0.2
Step-by-step explanation:
For many probabilities like this one, you have to add the total of materials or items together, even if they are different colors, shape, coin type, etc.
you have 12 pennies, 19 nickles, 14 dimes, and 15 quarters. This adds up to a total of 60 coins. Twelve of those are pennies.
You have twelve possible pennies to choose at random from a total of 60 in a bag.
So 12/60/ This simplifies to a probability of 1/5. If you divide 1 by 5 than it would be 0.2
The probability of choosing a penny from a bag of coins is 1/5, or 0.2.
Hope this helps
Answer:
yes , 33^2 + 56^2 = 65^2 and obtuse
Step-by-step explanation:
<h2><u>Question 3</u></h2>
make use of the Pythagoras theorem
which is :
c^2 = a^2 + b^2
where c is the hypotenuse.
now put the values in the equation
65^2 = 56^2 + 33 ^2
the answer is :
<u>yes , 33^2 + 56^2 = 65^2</u>
<u></u>
<h2><u>Question 4</u></h2>
<u />
note if :
c^2 = a^2 + b^2 ----------- right
c^2 < a^2 + b^2------------ acute
c^2 > a^2 + b^2------------- obtuse
hence :
16 + 30 > 38
therefore its : <u>obtuse </u>