First picture)
I: 5x+2y=-4
II: -3x+2y=12
add I+(-1*II):
5x+2y-(-3x+2y)=-4-12
8x=-16
x=-2
insert x=-2 into I:
5*(-2)+2y=-4
-10+2y=-4
2y=6
y=3
(-2,3)
question 6)
I: totalcost=115=3*childs+5*adults
II: 33=adults+childs
33-adults=childs
insert childs into I:
115=3*(33-adults)+5*adults
115=99-3*adults+5*adults
16=2*adults
8=adults
insert adults into II:
33-8=childs
25=childs
so it's the last option
question 7)
a) y<6 and y>2 can also be written as 2<y<6, so solution 3 exist for example
b) y>6 and y>2 can also be written as 2<6<y, so solution 7 exist for example
c) y<6 and y<2 inverse of b: y<2<6, so for example 1
d) y>6 and y<2: y<2<6<y, this is impossible as y can be only either bigger or smaller than 2 or 6
so it's the last option
question 8)
I: x+y=12
II: x-y=6
subtract: I-II:
x+y-(x-y)=12-6
2y=6
y=3
insert y into I:
x+3=12
x=9
(9,3)
question 9)
I: x+y=6
II: x=y+5
if you take the x=y+5 definition of II and substitute it into I:
(y+5)+y=6
which is the second option :)
Answer:
(-4x - 2)(-5x) + (-4x - 2)(3)
Step-by-step explanation:
Your polynomial is
(-4x - 2)(-5x + 3)
The distributive property states that
a(b + c) = ab + ac
Let a = -4x - 2. Then
(-4x - 2)(-5x + 3) = a(5x + 3) = a(-5x) + a(3)
Substitute the value of a.
a(-5x) + a(3) = (-4x - 2)(-5x) + (-4x - 2)(3)
You have just distributed the first binomial (-4x - 2) among the terms of the second binomial.
Answer:
1,400,000,000
Step-by-step explanation:
Since there are 7 billion people on the earth, you must divide 7,000,000,000 by 5 and you arrive at the answer of 1,400,000,000.
Hope that helps!
Answer:
x = -7
x = 5
Step-by-step explanation:
The standard form of quadratic equations is
Ax^2 + Bx + C = 0
The factors need to multiply together to be C and add together to be B.
The two numbers that will multiply together to be -35 and add together to be 2 are -5 & 7.
The factor pairs are (x+7)(x-5). Zero product property means we set each of those factor pairs = 0 and solve.
x + 7 = 0
-7 -7 Subtract 7 from each side to solve
x = -7
x - 5 = 0
+5 +5 Add 5 to each side to solve
x = 5
Considering the margin of error, it is found that the 95% confidence interval for the percentage of adults who say vaccines should be required is (64.9%, 71.1%).
<h3>What is a confidence interval?</h3>
It is given by the sample statistic plus/minus the margin of error.
In this problem, 68% of adults say such vaccines should be required, with a margin of error of 3.1%, hence:
68% - 3.1% = 64.9%.
68% + 3.1% = 71.1%.
The 95% confidence interval for the percentage of adults who say vaccines should be required is (64.9%, 71.1%).
More can be learned about confidence intervals at brainly.com/question/25890103
