Problem:
Solve
2
x
+
5
y
=
−
3
;
3
x
−
y
=
21
Steps:
I will try to solve your system of equations.
3
x
−
y
=
21
;
2
x
+
5
y
=
−
3
Step: Solve
3
x
−
y
=
21
for y:
3
x
−
y
+
−
3
x
=
21
+
−
3
x
(Add -3x to both sides)
−
y
=
−
3
x
+
21
−
y
−
1
=
−
3
x
+
21
−
1
(Divide both sides by -1)
y
=
3
x
−
21
Step: Substitute
3
x
−
21
for
y
in
2
x
+
5
y
=
−
3
:
2
x
+
5
y
=
−
3
2
x
+
5
(
3
x
−
21
)
=
−
3
17
x
−
105
=
−
3
(Simplify both sides of the equation)
17
x
−
105
+
105
=
−
3
+
105
(Add 105 to both sides)
17
x
=
102
17
x
17
=
102
17
(Divide both sides by 17)
x
=
6
Step: Substitute
6
for
x
in
y
=
3
x
−
21
:
y
=
3
x
−
21
y
=
(
3
)
(
6
)
−
21
y
=
−
3
(Simplify both sides of the equation)
Answer:
y
=
−
3
and
x
=
6
It's A because 7.5 is the starting point but it's not included so that point is circled.
Answer:
25 cm^2
Step-by-step explanation:
the area of 1 triangle is 20, so the missing length of the triangle is 5. 5x5=25
Y = -5x -5
To check, we can insert 0 for y and -1 for x
0 ? (-5X-1) - 5
0 ? 5 - 5
0 = 0
So yes, the equation is correct
A)
Let c be the number of right guesses.
the probability of c answers =.25 and probability of the wrong answer is 1-.25=.75
c distribution is in the parameter of (20, .25).
b) mean = 20 * .25== 5
c) p of c guess =.25 ^20 =9.095* 10 ^-13
d) p of 10 c guess =.014 or 1.4% it is not possible for him to have 10 right guess.
