Solve by elimination.
multiply the lower equation by negative 1.
-y=7x-21
-y+y=o
new equation is
7x+6-52=0
6-52 is -46
-7x=-46
divide by -7
x=6.57...
plug it back in
y= 7(6.57)+21
7*6.57= 46
y=46+21
y=67
(might be wrong, I tried)
65:x = 13:15
Divide 65 by 13.
65/13=5
Multiply 15 by 5 for the proportionate factor.
75.
There are 75 girls in the classroom.
We're looking for the total so we need to add 65 with 75.
65+75= 140.
There are 140 total students.
Looks like a transformation of x^2 where it is stretched vertically.
When x = 1 , f(x) = 4 and when x = 2 f(x) = 16
Yes its f(x) = 4x^2
Answer:
x - 15 ÷ 2
Step-by-step explanation:
Since it wants you to find the half of your answer after you find the difference, be sure to leave the two at the end of your equation. With that said, let's move into finding out what "the difference of a number and fifteen is". Whenever they tell you 'a number', it means they want you to put a variable, such as x, since you do not know the number and it could be any number. Now, the "difference" of something usually means...you guessed it, subtraction! Now that you've decoded your equation, you now know it means that x - 15 is the first part, and you can now put the one half right after it.
If this is confusing, I can explain further. :D
-/7? imagine that there is an -1 as the numerator. so now -/7 turns into -1/7