Answer:
since Sonia saved 45$ in 5 weeks and 70$ in 10 weeks. we are to find the amount she saved up in x weeks.
let's make the amount y
so x= y
5 = 45 cross multiplying the values
we then have 45x= 5y
y= 7x
x=y
10=70
10x = 70y
y= 7x = y=5x+ 20, y = 20x+5
Answer:

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Step-by-step explanation:
Let the number be x.

Dividing both sides by 4,

Subtracting 8 from both sides,

The number is -7.
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
Javier rode his bike for a total of 40 minutes.
Let x be the minutes Javier ride after lunch
Let y be the minutes Javier ride before lunch
The number of minutes he rode after lunch is 4 times the number of minutes he rode before lunch
x = 4 y
The number of minutes he rode after lunch + number of minutes he rode before lunch = 40
x + y = 40
We know x= 4y
4y + y = 40
5y = 40
y = 8
x= 4y so x= 4(8) = 32
Javier ride 32 minutes after lunch
Answer:
<h3>11.8 feet</h3>
Step-by-step explanation:
Given
Length of the ladder = 12foot
angle of elevation = 80 degrees
Required
Height of the wall (opposite side)
The set up will form a right angled triangle where
length of the ladder is the hypotenuse
height of the wall is opposite;
Using SOH, CAH, TOA trig identity
According to SOH
sin 80 = opp/hyp
sin80 = opp/12
opp = 12sin80
opp = 11.82 feet
Hence the height of the wall is 11.8feet (to the nearest tenth)