Answer:
paper clips = $1.85
index cards = $3.95
Step-by-step explanation:
Mark
12 paper clips = x
10 index cards = y
$61.70 total
Janice
15 paper clips = x
7 index cards = y
$55.40 total
12x + 10y = 61.70
15x + 7y = 55.40
*** you want to cancel out one of the letters
(12x + 10y = 61.70) * -7
(15x + 7y = 55.40) * 10
-84x -70y = -431.9
150x + 70y = 554.0
150x + 70y = 554.0
-84x -70y = -431.9
66x + 0 = 122.1
66x = 122.1
x = 122.1 ÷ 66
x = 1.85
plug it back in
15(1.85) + 7y = 55.40
27.75 + 7y = 55.40
7y = 55.40 - 27.75
7y = 27.65
y = 27.65 ÷ 7
y = 3.95
Answer:
b
Step-by-step explanation:
Justin's score has to be greater than 80. the appropriate inequality sign is >
Note that
> means greater than
< means less than
≥ means greater than or equal to
≤ less than or equal to
On the number line, since the score has to be greater than 80, the line would start from 80 and end on 95
> or < is represented by unfilled circle
≤ or ≥ is represented by filled circle
Answer is number one. The number inside the bracket is the time and the number after the equal sign is the height. As you can see, at t=5, height=75.
Rearrange x²+y²-4x+6y=-11 I'll tell you an easy way. take the coefficient of x and divide it by -2 and the coefficient of y and divide it by -2 so -4 ÷-2 = 2 6÷-2= -3 (2,-3) is the center of the circle to know the radius √2² + -3² + -11 =√2 The Radius equals √2
