79.4k views
5 votes
PLEASE help with these math questions

PLEASE help with these math questions-example-1
PLEASE help with these math questions-example-1
PLEASE help with these math questions-example-2
PLEASE help with these math questions-example-3
PLEASE help with these math questions-example-4
PLEASE help with these math questions-example-5
User Thomasvdb
by
8.3k points

1 Answer

4 votes
all of these are applications of the distance formula
remember a^2+b^2=c^2
so the distance (c) is
\sqrt{a^(2)+b^(2)}
a and b are legnths of legs so we find the legnths


the distance between points (x1,y1) and (x2,y2) is

D=
\sqrt{(x2-x1)^(2)+(y2-y1)^(2)}
input points and find distance

1. (3,5) ot (7,3)
D=
\sqrt{(7-3)^(2)+(3-5)^(2)}=√(16+4)=√20=4.47
answer is A

2. (-3,-2) to (4,6)
D=
\sqrt{(4-(-3))^(2)+(6-(-2))^(2)}=√(49+64)=√113=10.63
answer is 10.6 units

3. from (1,7) to (9,-2)
D=
\sqrt{(9-1)^(2)+(-2-7)^(2)}=√(64+81)=√145=12.04
answer is B

4. (-1,-2) to (6,2)
D=
\sqrt{(6-(-1))^(2)+(2-(-1))^(2)}=√(49+16)=√65=8.06
round
8.1 units

5. apply multipule times
A=(2,2)
B=(12,2)
C=(9,8)
D=(2,8)
find the distance between
A to B
B to C
C to D
D to A
we can see the distances between AB, CD and AD easily
just since 1 variable doesn't change, we just find the change in the other variable
AB=10 units
CD=7 units
DA=6 units
now
CB is from (12,2) to (9,8)
D=
\sqrt{(9-12)^(2)+(8-2)^(2)}=√(9+36)=√45=6.7

add everybody
AB+BC+CD+DA=10+6.7+7+6=29.7
we see that they put a trick and see option D, the not careful people will chose that but the quesiton askes for the perimiter

answer is B
User Asidd
by
7.2k points