Roosevelt used the technology of radio to restore the nations confidence which president used the technology of television to do same thing

The president who used the technology of television to restore the nations confidence was Jimmy Carter. In 1979, the President Jimmy Carter addressed a nation via live television to deal with the nation’s energy crisis and the recession they were facing.

Jimmy Carter was the 39th president of the United States who struggled to respond to severe challenges, such as a major energy crisis along with high inflation and unemployment.

the perimeter of a triangle is 69 cm. side a is 5 cm shorter than side b. side c is twice as long as side a. find the length of each side. i need to know how to do it in 2 equations.  

equations:

a = b-5

c = 2a

a + b + c = 69