Answer: x= 9y - 77 its vertical intercep 0, -77
Answer:
to estimate the result of multiplication (product), round the numbers to some close numbers that you can easily multiply mentally. One method of estimation is to round all factors to the biggest digit (place value) they have.
Step-by-step explanation:
So
y=ax^2+bx+c
(x,y)
sub the points and solve
(4.28,6.48)
6.48=a(4.28)^2+b(4.28)+c
(12.61,15.04)
15.04=a(12.61)^2+b(12.61)+c
well, for 3 variables, we need equations and therefor 3 points
maybe we are supposed to assume it starts at (0,0)
so then
0=a(0)^2+b(0)+c
0=c
so then
6.48=a(4.28)^2+b(4.28)
15.04=a(12.61)^2+b(12.61)
solve for a by subsitution
first equation, minut a(4.28)^2 from both sides
6.48-a(4.28)^2=b(4.28)
divide both sides by 4.28
(6.48/4.28)-4.28a=b
sub that for b in other equation
15.04=a(12.61)^2+b(12.61)
15.04=a(12.61)^2+((6.48/4.28)-4.28a)(12.61)
expand
15.04 =a(12.61)^2+(81.7128/4.28)-53.9708a
minus (81.7128/4.28) both sides
15.04-(81.7128/4.28)=a(12.61)^2-53.9708a
15.04-(81.7128/4.28)=a((12.61)^2-53.9708)
(15.04-(81.7128/4.28))/(((12.61)^2-53.9708))=a
that's the exact value of a
to find b, subsitute to get
(6.48/4.28)-4.28((15.04-(81.7128/4.28))/(((12.61)^2-53.9708)))=b
if we aprox
a≈-0.038573167896199
b≈1.6791118501845
so then the equation is
y=-0.038573167896199x²+1.6791118501845x
Answer:
BC = 6.8
Step-by-step explanation:
The distance from A to B, then from B to C, is the same distance as from A to C.
Thus,
AB + BC = AC
AB = 8x + 8
BC = 4x + 2
AC = 22
AB + BC = AC
(8x + 8) + (4x + 2) = 22
Expanding the parenthesis:
8x + 8 + 4x + 2 = 22
8x + 4x + 8 + 2 = 22
12x + 12 = 22
Subtracting 12 from both sides:
12x = 10
Dividing both sides by 12:
x = 10/12 = 1.2
x = 1.2
We're looking for BC. As we know,
BC = 4x + 2
Let's now put in x = 1.2 into this equation:
BC = 4x + 2
BC = 4 * 1.2 + 2
Since 4 * 1.2 is 4.8:
BC = 4.8 + 2
BC = 6.8
Answer: BC = 6.8
