When subtracting a number from a negative (like question one) the subtraction sign will now be an addition sign.
1.
6-(-7)=13
For question 2, its simple subtraction. If you subtract a negative from positive, it'l be a negative.
2.
-3 - 3= -6
3.
-15 - 23 = -38
Now we combine my previous explanations. Subtracting a negative from a negative will be like adding (like in question 4)
4.
-9 - (-5)= -4
5.
5 - (-15)=20
6.
78-(-17)=95
Extra Info:
When adding a number (doesnt matter if positive or negative) to a negative it will turn into subtraction.
Examples:
6+(-9)=-3
-9+(-9)= -18
Answer:
23
Step-by-step explanation:
With f(4), we plug 4 into the function.
f(4) = 4² + 7
f(4) = 16 + 7
f(4) = 23
Answer: $24.19
Step-by-step explanation:
From the question, we are informed that Mai bought gas for her car which cost $2.95 per gallon and that she bought 8.2 gallons.
The total cost for Mai's gas will be:
= $2.95 × 8.2
= $24.19
Step-by-step explanation: A coordinate grid has two perpendicular lines, or axes (pronounced AX-eez), labeled just like number lines. The horizontal axis is usually called the x-axis. The vertical axis is usually called the y-axis. The point where the x- and y-axis intersect is called the origin
<h3>Rate of the boat in still water is 70 km/hr and rate of the current is 15 km/hr</h3><h3><u>Solution:</u></h3>
Given that,
A motorboat travels 165 kilometers in 3 hours going upstream and 510 kilometers in 6 hours going downstream
Therefore,
Upstream distance = 165 km
Upstream time = 3 hours
<h3><u>Find upstream speed:</u></h3>
Thus upstream speed is 55 km per hour
Downstream distance = 510 km
Downstream time = 6 hours
<h3><u>Find downstream speed:</u></h3>
Thus downstream speed is 85 km per hour
<em><u>If the speed of a boat in still water is u km/hr and the speed of the stream is v km/hr, then</u></em>
Speed downstream = u + v km/hr
Speed upstream = u - v km/hr
Therefore,
u + v = 85 ----- eqn 1
u - v = 55 ----- eqn 2
Solve both
Add them
u + v + u - v = 85 + 55
2u = 140
u = 70
<em><u>Substitute u = 70 in eqn 1</u></em>
70 + v = 85
v = 85 - 70
v = 15
Thus rate of the boat in still water is 70 km/hr and rate of the current is 15 km/hr
