Answer:
80 hours
Step-by-step explanation:
let d represent doug, let l represent laura
first, set up a system of equations representing the problem:
since doug spent 10 less than twice the hours laura did, and we know that the total amount of hours they spent together is 230:
l=2d+10
d+l=230
then solve:
*first i rearranged the equations so i can solve this system of equations using elimination method*
l-2d=10
l+d=230
*subtract*
3d=240
d=80
so, doug spent 80 hours in the lab
Answer:
A= 21 m
Step-by-step explanation:
The correct answer is 8.
Hope this helped!
Answer:
A and b
Step-by-step explanation: Because ....
Answer:
X=140
Step-by-step explanation:
<em>Firstly, any Quadrilateral has a total sum of its angle equal to 360 degrees</em>
<em>The attachment you are showing us shows that we already know two angles</em>
<em>(70)&(60) degrees. I am assuming the line DC is a tangent, so angle ADC must be 90 degrees since a full angle on a tangent is equal to 180 degrees and there is 90 from the other side (180-90=90). Now we know 3 angles and what you have to do is find X so that when you add them all up they make a sum of 360. </em>
<em />
X+70+60+90=360
X=360-70-60-90
X=140
