The answer is C because you already know that if plus sign we have to count in back of the number so.. the answer is 7.02 x 10^3
8x+16y = 39 and 40x+8y = 42 are the system of equations that represents in inches the relationship between the length of a blue tile and the length of a white tile.
<u>Step-by-step explanation</u>:
Let 'x' be the inches of a blue tile.
Let 'y' be the inches of a white tile.
8x+16y = 39 -------(1)
40x+8y = 42 -------(2)
Multiply eqn(2) by 2 and subtract it from eqn(1)
8x+16y = 39
(-) <u>80x+16y = 84</u>
<u>-72x = -45 </u>
⇒ x = -45/-72
⇒ x = 5/8
∴ Blue tile is 5/8 inches.
substitute x=5/8 in eqn(1)
⇒ 8(5/8) + 16y = 39
⇒ 16y = 39-5
⇒ y =34/16
⇒ y = 17/8
∴ White tile is 17/8 inches.
So let's start with the slope-intercept form of a linear equation. That is y = mx+b where m is slope and b is the y intercept. But, this is an inequality. So first we have to look at the way the graph is shaded. Since it is shaded upwards, you know that it is in the form of y ≥ mx + b. It tells you that the y-intercept is c because the line hits the y-axis at (0,c). Hence the equation is now y ≥ mx + c. But now, we have to find the slope of the graph. This is found by "rise over run" (I am sure you have heard of this). Count how many units the graph went down/up and how many units the graph went left/right and put it in fraction form of (units down or up) / (units left or right). Well it moves 2 units down so plug -2 into the top. It moved 1 unit right, so plug +1 into the denominator. So, the slope is -2. Hence we finally have our formula: y ≥ -2x + c which is the 5th choice.
Answer:
Answer as a decimal:
Answer as a fraction:
Step-by-step explanation:
y - 15 = 3x
-2x + 5y = -3
Solve the first equation first to substitute into second equation
y - 15 = 3x
Add 15 to both sides of the equation
y = 3x + 15
Substitute this value of y into second equation
-2x + 5y = -3
2x + 5(3x + 15) = -3
Multiply
2x + 15x + 75 = -3
Add the x's
17x + 75 = -3
Subtract 75 from both sides of the equation
17x = -78
Divide both sides of the equation by 17
Answer as a decimal:
Answer as a fraction:
Hope this helps :)