Answer:
9x - 15
Step-by-step explanation:
3[(x-5)+2x]
3(3x -5)
= 9x - 15
tadah!
So for this i would always drop the decimal from the number so it will be 796 ÷ 5 which would be 159.2 so the was two numbers in the original problem over from the decimal would be put back in the answer. so you would put the decimal in over two times so the answer will be 1.592
Very complex, you should ask each individual question, or give more points
general strategy:
get 1 side to equal 0
factor
set each factor to 0
solve
1. factor out the x and set each to zero
x(x+7)=0
x=0
x+7=0
subtract 7
x=-7
x=0 or -7
2. factor out the 6s
6s(s+3)=0
6s=0
s=0
s+3=0
subtract 3
s=-3
s=-3 or 0
3. I'm assuming that the equation was supposed to be t^2+8t+16 so
find what 2 numbers multiply to get 16 and add to get 8
the numbers are 4 and 4
factor
(x+4)(x+4)=0
x+4=0
subtract 4
x=-4
4. find what 2 numbers multipy to get 25 and add to get -10
the numbers are -5 and -5
factor
(x-5)(x-5)=0
set each to zero
x-5=0
add 5
x=5
5. subtract 16 from both sides
h^2+6h-16=0
find what 2 numbers multiply to get -16 and add to get 6
the numbers are -6 and 10
factor
(h-6)(h+10)=0
set each to zero
h-6=0
add 6
h=6
h+10=0
subtract 10
h=-10
h=-10 or 6
6.subtract 5x from both sides
x^2-5x-14=0
find what 2 numbers multiply to get -14 and add to get -5
the numbers are -7 and 2
factor
(x-7)(x+2)=0
set each to zero
x-7=0
add 7
x=7
x+2=0
subtract 2
x=-2
x=-2 or 7
7.add 2r^2 to both sides
2r^2+11r+15=0
difficult so multiply 2 and 15 and get 30
not factor and find what 2 numbers multiply to get 30 and add to get 11
the numbers are 5 nd 6
split 11 up into 5 and 6
2r^2+6r+5r+15=0
group and factor
(2r^2+6r)+(5r+15)=0
factor
2r(r+3)+5(r+3)=0
reverse distribute
(2r+5)(r+3)=0
set each to zero
2r+5=0
subtract 5
2r=-5
divide 2
r=-5/2
r+3=0
subtract 3
r=-3
r=-3 or -5/2
8. this is a difference of 2 perfect squares in which if you have
x^2-y^2 that factors out of (x-y)(x+y) so
x^2-25=0
x^2-5^2=0
(x-5)(x+5)=0
set each to zero
x-5=0
add 5
x=5
x+5=0
subtract 5
x=-5
x=-5 or 5
9. differnce of 2 perfect squares
81-4x^2=0
9^2-(2x)^2=0
(9-2x)(9+2x)=0
set each to zero
9-2x=0
add 2x to both sides
9=2x
divde 2
9/2=x
9+2x=0
subtract 9 from both sidees
2x=-9
divide 2
x=-9/2
x=-9/2 or 9/2
10. subtract 12s from both sides
4s^2-12s+9=0
multiply 4 and 9 and get 36
find what 2 numbers multiply to get 36 and add to get -12
the numbers are -6 and -6
split up the -12s into -6s and -6s
4s^2-6s-6s+9=0
group
(4s^2-6s)+(-6s+9)=0
factor
2s(2s-3)+(-3)(2s-3)=0
reverse distribute
(2s-3)(2s-3)=0
set each to zero
2s-3=0
add 3
2s=3
divide 2
s=3/2
ANWERS:
1. x=0 or -7
2. s=-3 or 0
3. x=-4
4. x=5
5. h=-10 or 6
6. x=-2 or 7
7. r=-3 or -5/2
8. x=-5 or 5
9. x=-9/2 or 9/2
10. s=3/2
Answer:
(2/3, 13/3) (Exactly one solution)
Step-by-step explanation:
Write these equations in a column:
x+y=5
2x-y=-3
Note that we can eliminate y immediately by adding these two equations together. We get:
3x = 2, so that x = 2/3.
Substituting 2/3 for x in the first equation, we get:
2/3 + y = 5. Clear out fractions by multiplying all three terms by 3:
2 + 3y = 15, or 3y = 13. Then y = 13/3, and the solution is
(2/3, 13/3) There is exactly one solution.
855 divided by 45 is19 hope dis helped